Here, I'll detail all episodes that have aired, and provide guest star names.
Early Shorts/Season 1
FROSTY
In this very early short, crude versions of Cartman (who's called Kenny), the real Kenny, Stan, and Kyle build a snowman which magically comes to life after putting a magic hat on it. The snowman tries to kill them, and manages to kill Kenny and the "other Kenny" (Cartman). Note: Kenny says "yeah" and "no" in this and it's not muffled!
THE SPIRIT OF CHRISTMAS (Soxmas)
SOXMAS is the one that started the whole South Park phenomenon. It features the boys cheering on Jesus and Santa as they duke it out for the meaning of Christmas.
Ep. 101: CARTMAN GETS AN ANAL PROBE
In the series debut, Cartman is abducted by aliens, and they discover Kyle's little brother has been kidnapped by the same aliens.

Ep. 102: WEIGHT GAIN 4000
Cartman cheats and wins on a national essay contest, and Kathie Lee Gifford comes to present the award. But Mr. Garrison has a bone to pick with Kathie Lee...
Ep. 103: VOLCANO
It is discovered that a mountain in South Park is actually a volcano about to erupt, and the boys are hunting with Stan's Uncle Jimbo on the same mountain...
Ep. 104: BIG GAY AL'S BIG GAY BOAT RIDE
Stan's inability to cope with his dog's homosexuality seriously affects his football team's ability to beat an opposing town's team.

Ep. 105: AN ELEPHANT MAKES LOVE TO A PIG
The boys attempt to cross-breed an elephant and a pig for a science fair project.
Ep. 106: DEATH
The boys help summon the Grim Reaper to take Stan's suicidal grandfather, as the adults protest a flatulence-based cartoon, which just happens to be the most popular show in town.
Ep. 107: PINKEYE
In the Halloween Special (and horror movie spoof), zombies take over South Park and only Kyle, Stan and Cartman can stop them.

Ep. 109: STARVIN' MARVIN
A starving Ethiopian boy is sent to the boys instead of a sports watch, as Government officials mistakenly take Cartman to Ethiopia trying to return the boy.
Ep. 110: MR. HANKY, THE CHRISTMAS POO
Kyle's loneliness due to being Jewish during Christmas time quickly subsides when his fecal friend Mr. Hanky comes to spread joy to South Park.
Ep. 108: DAMIEN
The son of Satan is a new student at South Park Elementary, while his dad fights Jesus one-on-one for world domination. Meanwhile, Cartman's birthday is overshadowed by the fight and Cartman does everything he can to get people to go to his party instead.

Ep. 111: TOM'S RHINOPLASTY
While Mr. Garrison gets a nose job, a hot new substitute comes and wins the attention of the boys. Wendy tries to get Stan's attention back onto her. Guest voice: Natasha Henstrige.
Ep. 112: MECHA-STREISAND
Barbra Streisand tries to get a magical amulet from the boys to give her evil powers. Guest Voice: Robert Smith of The Cure.
Ep. 113: CARTMAN'S MOM IS A DIRTY SLUT
When Cartman exhibits strange behavior, he realizes he must find his father. Guest Voice: Jay Leno as "Kitty."

Season 2

Ep. 201: NOT WITHOUT MY ANUS
In this Terrence and Phillip special, Terrence and Phillip rescue Terrence's bastard offspring (whose mother is Celine Dion) while inadvertently triggering Canada's defeat in Iraq's takeover of that country.
Ep. 202: CARTMAN'S MOM IS A DIRTY SLUT, PART II-
Just before revealing who Cartman's father is, mad scientist Mephesto is shot, and driven to a bad hospital. Meanwhile, while filming a recreation of the event for America's Most Wanted, the townspeople get snowed in...
Ep. 203: CHICKEN LOVER
Officer Barbrady is illiterate, so he hires junior deputies Stan, Kyle, Kenny and Cartman to fill in for him while he goes back to school. Meanwhile, a new police case involves raping of chickens.

Ep. 204: IKE'S WEE-WEE
Kyle tries to protect his little brother when they learn his bris is coming up, because the boys have misinterpreted it as penis- chopping. Meanwhile, Mr. Mackey is fired and becomes a hippie/junkie. Ep. 205: CONJOINED FETUS LADY
South Park Elementary's dodgeball team has made it to the championships in China where they have to face off with a skilled home team. Meanwhile, back in South Park, the town finds out that the nurse at South Park Elementary has a dead baby fetus stuck the side of her head. The whole town makes a big deal out of it and try to make her feel better about her disability with parades and stupid hats which, in effect, made her feel worse.
Ep. 206: THE MEXICAN STARING FROG FROM SOUTHERN SRI LANKA
The boys are asked to do a school report on Vietnam, so they ask Vietnam vets Jimbo and Ned about the war. Jimbo and Ned's version of the war includes carnival rides, and they claim to have defeated the whole Viet Cong army. When they present this to the class, Mr. Garrison doesn't buy the story and gives them an F. The boys try to get back at them by making fake videos of a strange creature (when you stare at it you go blind) to put on Jimbo and Ned's hunting TV show. They then visit Jesus and Pals which is made up to look like Jerry Springer.

Ep. 207: FLASHBACKS
The boys are trapped on a bus on the edge of a cliff, and begin to reminisce about scenes from past episodes. Only the scenes are totally distorted and everyone ends up eating ice cream in the end. Meanwhile, Ms. Crabtree's yelling is mistaken for a comedy bit and she skyrockets to stardom.
Ep. 208: SUMMER SUCKS
The boys, to their disappointment, find that fireworks have been outlawed in Colorado. Jimbo and Ned head south of the border to buy some, while the town plans to set off the world's largest snake on July 4th. Meanwhile, Mr. Garrison can't find Mr. Hat.
Ep. 209: CHEF'S SALTY CHOCOLATE BALLS
A film festival comes to South Park, and transforms it into a huge city, disrupting the state of peace it was once in. Meanwhile, Mr. Hankey returns, and, since he lives in the sewers, is getting more pollution than he can live in from the population above, and needs Kyle to stop them.

Ep. 210:CHICKENPOX
The boys suspect their parents gave them chickenpox on purpose.
Ep. 211: ROGER EBERT SHOULD LAY OFF THE FATTY FOODS
The boys uncover suspicious goings-on at the local planetarium, and Cartman is chosen as a spokesperson for Cheesy Poofs!
Ep. 212: CLUBHOUSES:
The kids build rival clubhouses to play truth or dare, and it is revealed Bebe has a crush on Kyle, but at the end, she goes out with Clyde. Also, Stan's parents split up and Stan is faced with a jerk stepfather.

Ep. 213: COW DAYS:
South Park's annual Running of the Cows is upon us, but the cows won't come out to chase people. Kyle and Stan meanwhile try to win a Terrence and Phillip doll at the fair, while Cartman, forced to get money for Stan and Kyle, gets a bump on the head and thinks he's a Vietnamese hooker (really!). Ep. 214: CHEF AID: The boys hold a benefit concert for Chef after he is sued wrongfully. A ton of stars appear, including Primus, Elton John, Rancid, and more. The album will be a spin-off of this episode. Meanwhile, Mr. Hat comes back and forces Mr. Garrison to choose between him and Mr. Twig. Ep. 215: SPOOKYFISH: Stan's aunt buys him a fish, who starts to kill everyone in South Park. Meanwhile, the boys are suspicious when Cartman begins acting nice. They discover that there are two Cartmans, and the only way to tell them apart is the nice one wears a fake goatee.

Ep. 216: MERRY CHRISTMAS, CHARLIE MANSON: It's a very Cartman Christmas when the boys go to his relative's house, and find that Cartman's uncle has broken out of prison with homicidal maniac Charles Manson and is hiding out there. Meanwhile, Kyle discovers that Mr. Hankey has become a modern commercial product, instead of the original icon he was. Ep. 217: GNOMES: It's up to Stan, Cartman, Kenny, and Kyle to save a local coffee shop from being driven out of business, and they get some help from some underpants-stealing gnomes. Ep. 218: PREHISTORIC ICE MAN: The boys accidentally discover a frozen "caveman" actually from 1996. A fight over naming him tears Kyle and Stan's friendship apart, while Cartman adopts an Australian hunter persona.
Ep. 301: RAINFOREST, SCHMAINFOREST: The boys are forced to travel to Costa Rica with the "Getting Gay with Kids Choir." But when they're lost in the rain forest, they develop "respect" for nature. GUEST VOICE: Jennifer Aniston as the hippie do-gooder teacher. Ep. 302: SPONTANEOUS COMBUSTION: The boys re-enact the Stations of the Cross, with Cartman as Jesus. Also, Stan's father is blamed for a rash of spontaneous combustion in South Park that's caused by holding in farts. Ep. 303: CHEF'S MOMMA: Chef falls in love and makes plan for marraige with a woman the boys discover is a succubus, a beautiful demon that attempts to steal people's souls by putting a spell on them.

FROSTY In this very early short, crude versions of Cartman (who's called Kenny), the real Kenny, Stan, and Kyle build a snowman which magically comes to life after putting a magic hat on it. The snowman tries to kill them, and manages to kill Kenny and the "other Kenny" (Cartman). Note: Kenny says "yeah" and "no" in this and it's not muffled!	THE SPIRIT OF CHRISTMAS (Soxmas) SOXMAS is the one that started the whole South Park phenomenon. It features the boys cheering on Jesus and Santa as they duke it out for the meaning of Christmas.	Ep. 101: CARTMAN GETS AN ANAL PROBE In the series debut, Cartman is abducted by aliens, and they discover Kyle's little brother has been kidnapped by the same aliens.
Ep. 102: WEIGHT GAIN 4000 Cartman cheats and wins on a national essay contest, and Kathie Lee Gifford comes to present the award. But Mr. Garrison has a bone to pick with Kathie Lee...	Ep. 103: VOLCANO It is discovered that a mountain in South Park is actually a volcano about to erupt, and the boys are hunting with Stan's Uncle Jimbo on the same mountain...	Ep. 104: BIG GAY AL'S BIG GAY BOAT RIDE Stan's inability to cope with his dog's homosexuality seriously affects his football team's ability to beat an opposing town's team.
Ep. 105: AN ELEPHANT MAKES LOVE TO A PIG The boys attempt to cross-breed an elephant and a pig for a science fair project.	Ep. 106: DEATH The boys help summon the Grim Reaper to take Stan's suicidal grandfather, as the adults protest a flatulence-based cartoon, which just happens to be the most popular show in town.	Ep. 107: PINKEYE In the Halloween Special (and horror movie spoof), zombies take over South Park and only Kyle, Stan and Cartman can stop them.
Ep. 109: STARVIN' MARVIN A starving Ethiopian boy is sent to the boys instead of a sports watch, as Government officials mistakenly take Cartman to Ethiopia trying to return the boy.	Ep. 110: MR. HANKY, THE CHRISTMAS POO Kyle's loneliness due to being Jewish during Christmas time quickly subsides when his fecal friend Mr. Hanky comes to spread joy to South Park.	Ep. 108: DAMIEN The son of Satan is a new student at South Park Elementary, while his dad fights Jesus one-on-one for world domination. Meanwhile, Cartman's birthday is overshadowed by the fight and Cartman does everything he can to get people to go to his party instead.
Ep. 111: TOM'S RHINOPLASTY While Mr. Garrison gets a nose job, a hot new substitute comes and wins the attention of the boys. Wendy tries to get Stan's attention back onto her. Guest voice: Natasha Henstrige.	Ep. 112: MECHA-STREISAND Barbra Streisand tries to get a magical amulet from the boys to give her evil powers. Guest Voice: Robert Smith of The Cure.	Ep. 113: CARTMAN'S MOM IS A DIRTY SLUT When Cartman exhibits strange behavior, he realizes he must find his father. Guest Voice: Jay Leno as "Kitty."
Season 2
Ep. 201: NOT WITHOUT MY ANUS In this Terrence and Phillip special, Terrence and Phillip rescue Terrence's bastard offspring (whose mother is Celine Dion) while inadvertently triggering Canada's defeat in Iraq's takeover of that country.	Ep. 202: CARTMAN'S MOM IS A DIRTY SLUT, PART II- Just before revealing who Cartman's father is, mad scientist Mephesto is shot, and driven to a bad hospital. Meanwhile, while filming a recreation of the event for America's Most Wanted, the townspeople get snowed in...	Ep. 203: CHICKEN LOVER Officer Barbrady is illiterate, so he hires junior deputies Stan, Kyle, Kenny and Cartman to fill in for him while he goes back to school. Meanwhile, a new police case involves raping of chickens.
Ep. 204: IKE'S WEE-WEE Kyle tries to protect his little brother when they learn his bris is coming up, because the boys have misinterpreted it as penis- chopping. Meanwhile, Mr. Mackey is fired and becomes a hippie/junkie.	Ep. 205: CONJOINED FETUS LADY South Park Elementary's dodgeball team has made it to the championships in China where they have to face off with a skilled home team. Meanwhile, back in South Park, the town finds out that the nurse at South Park Elementary has a dead baby fetus stuck the side of her head. The whole town makes a big deal out of it and try to make her feel better about her disability with parades and stupid hats which, in effect, made her feel worse.	Ep. 206: THE MEXICAN STARING FROG FROM SOUTHERN SRI LANKA The boys are asked to do a school report on Vietnam, so they ask Vietnam vets Jimbo and Ned about the war. Jimbo and Ned's version of the war includes carnival rides, and they claim to have defeated the whole Viet Cong army. When they present this to the class, Mr. Garrison doesn't buy the story and gives them an F. The boys try to get back at them by making fake videos of a strange creature (when you stare at it you go blind) to put on Jimbo and Ned's hunting TV show. They then visit Jesus and Pals which is made up to look like Jerry Springer.
Ep. 207: FLASHBACKS The boys are trapped on a bus on the edge of a cliff, and begin to reminisce about scenes from past episodes. Only the scenes are totally distorted and everyone ends up eating ice cream in the end. Meanwhile, Ms. Crabtree's yelling is mistaken for a comedy bit and she skyrockets to stardom.	Ep. 208: SUMMER SUCKS The boys, to their disappointment, find that fireworks have been outlawed in Colorado. Jimbo and Ned head south of the border to buy some, while the town plans to set off the world's largest snake on July 4th. Meanwhile, Mr. Garrison can't find Mr. Hat.	Ep. 209: CHEF'S SALTY CHOCOLATE BALLS A film festival comes to South Park, and transforms it into a huge city, disrupting the state of peace it was once in. Meanwhile, Mr. Hankey returns, and, since he lives in the sewers, is getting more pollution than he can live in from the population above, and needs Kyle to stop them.
Ep. 210:CHICKENPOX The boys suspect their parents gave them chickenpox on purpose.	Ep. 211: ROGER EBERT SHOULD LAY OFF THE FATTY FOODS The boys uncover suspicious goings-on at the local planetarium, and Cartman is chosen as a spokesperson for Cheesy Poofs!	Ep. 212: CLUBHOUSES: The kids build rival clubhouses to play truth or dare, and it is revealed Bebe has a crush on Kyle, but at the end, she goes out with Clyde. Also, Stan's parents split up and Stan is faced with a jerk stepfather.
Ep. 213: COW DAYS: South Park's annual Running of the Cows is upon us, but the cows won't come out to chase people. Kyle and Stan meanwhile try to win a Terrence and Phillip doll at the fair, while Cartman, forced to get money for Stan and Kyle, gets a bump on the head and thinks he's a Vietnamese hooker (really!).	Ep. 214: CHEF AID: The boys hold a benefit concert for Chef after he is sued wrongfully. A ton of stars appear, including Primus, Elton John, Rancid, and more. The album will be a spin-off of this episode. Meanwhile, Mr. Hat comes back and forces Mr. Garrison to choose between him and Mr. Twig.	Ep. 215: SPOOKYFISH: Stan's aunt buys him a fish, who starts to kill everyone in South Park. Meanwhile, the boys are suspicious when Cartman begins acting nice. They discover that there are two Cartmans, and the only way to tell them apart is the nice one wears a fake goatee.
Ep. 216: MERRY CHRISTMAS, CHARLIE MANSON: It's a very Cartman Christmas when the boys go to his relative's house, and find that Cartman's uncle has broken out of prison with homicidal maniac Charles Manson and is hiding out there. Meanwhile, Kyle discovers that Mr. Hankey has become a modern commercial product, instead of the original icon he was.	Ep. 217: GNOMES: It's up to Stan, Cartman, Kenny, and Kyle to save a local coffee shop from being driven out of business, and they get some help from some underpants-stealing gnomes.	Ep. 218: PREHISTORIC ICE MAN: The boys accidentally discover a frozen "caveman" actually from 1996. A fight over naming him tears Kyle and Stan's friendship apart, while Cartman adopts an Australian hunter persona.
Ep. 301: RAINFOREST, SCHMAINFOREST: The boys are forced to travel to Costa Rica with the "Getting Gay with Kids Choir." But when they're lost in the rain forest, they develop "respect" for nature. GUEST VOICE: Jennifer Aniston as the hippie do-gooder teacher.	Ep. 302: SPONTANEOUS COMBUSTION: The boys re-enact the Stations of the Cross, with Cartman as Jesus. Also, Stan's father is blamed for a rash of spontaneous combustion in South Park that's caused by holding in farts.	Ep. 303: CHEF'S MOMMA: Chef falls in love and makes plan for marraige with a woman the boys discover is a succubus, a beautiful demon that attempts to steal people's souls by putting a spell on them.