Following the discussion over on the 'What irritates you?' thread, I've decided to set up a separate thread to discuss this matter.

My least favourite episodes are Lisa the Iconoclast and the Boys of Bummer. There are others I'm not terribly keen on, but those are the two that come immediately to mind.

Any other thoughts?

My best one is "Who Shot Mr Burns"... two part episodes (and I think the only one to date...)

Probably one of the episodes where Sideshow Bob wants to kill Bart

Certified Simpsons geek here, so prepare for a long post!

I'm a huge fan of the Simpsons. There's something about this show that other similar shows - i.e. Seth McFarlane's cavalcade of cartoon "comedy" (admittedly I rather enjoy American Dad). I think it's the fact that we have a family of likeable characters (at least in the early seasons). The characters in Family Guy aren't very likeable, though I kinda like Stewie. (I don't hate Family Guy ever; the first few seasons are quite decent, though nowhere near the level of The Simpsons.)

I'll give a season-by-season introspect. Why not.

Season 1: Not a popular season, by any means. People complain about the animation, but as a fan of classic animation, I like the less off-model look. A few of the episodes this season are boring, but the show was finding its footing, and I enjoyed all thirteen episodes.

Favourites: Simpsons Roasting on an Open Fire, Bart the Genius, Bart the General, Moaning Lisa, Krusty gets Busted

Season 2: For me, the beginning of the golden-era of The Simpsons. The shows are funnier, the animation has improved and there's some real nice stories this season. An underrated classic season.

Favourites: Bart Gets an F, Itchy & Scrathcy & Marge, One Fish Two Fish Blow Fish Blue Fish, Oh Brother, Where Art Thou, Three Men and a Comic Book

Season 3: Most people pinpoint this as the start of the golden-era, and I think they're late. An improvement on Season 2, though. Lots of classics.

Favourites: Like Father, Like Clown, Radio Bart, Bart the Lover, Homer at the Bat, Black Widower, Oh Brother, Can You Spare Two Dimes?

Season 4: Another solid season, not sure if I like 4 or 3 better. Nah, I'll stick with 4. So many classic episodes. Heck, even the clip-show is good!

Favourites: A Streetcar Named Marge, Homer the Heretic, Itchy & Scratchy: The Movie, Lisa's First Word, I Love Lisa, Duffless.

Season 5: This begins my favourite two years of The Simpsons. Everything starts to get sillier, and funnier, in my opinion. Probably because of the show-runner of seasons 5 and 6 (forgot his name.) Still lots of heartfelt moments, though.

Favourites: Cape Feare, Homer Goes to College, Rosebud, Bart Gets Famous, Lisa vs Malibu Stacy, The Boy Who Knew Too Much

Season 6: My favourite season of The Simpsons. The silliness is still there, but there's some really nice episodes with some touching moments. True characters, that family. Apart from the clip show. Every episode is amazing.

Favourites: Sideshow Bob Roberts, Bart's Girlfriend, Homer Badman, Homie the Clown, A Star is Burns, Lisa's Wedding, Lemon of Troy, Who Shot Mr. Burns duology

Season 7: New show runners, show is still awesome, but some bland episodes start to appear half-way during the season. Episodes like 'Two Bad Neighbours', 'Bart the Fink', and 'Lisa the Iconoclast' are rather boring, but this season benefits from a very strong beginning and some nice episodes towards the end.

Favourites: Radioactive Man, Home Sweet Home Diddly Dum Doodily, Bart Sells His Soul, King-Size Homer, The Day the Violence Died, 22 Short Films About Springfield, Summer of 4'2".

Season 8: The show starts to decline a bit here. Still classic, in my eyes, but the attack of the bland episodes is imminent. 'The Canine Mutiny' is by far the most boring episode yet.

Favourites: You Only Move Twice, A Milhouse Divided, Mountain of Madness, That Mary Poppins Episode, Itchy and Scratchy and Poochie Show, Brother from Another Series, Homer's Enemy.

Season 9: The start of the reviled Scully era. Four years of controversial episodes. The Scully 'rot' hasn't sunk in yet, with some very fun episodes. But it's clear the show was declining. Perhaps the last classic season for me.

Favourites: Lisa's Sax, Realty Bites, The Joy of Sect, Lisa the Simpson, Girly Edition, King of the Hill.

Season 10: Man. The wackiness ensues. There are some real stinkers in this one, so I'm introducing the lowlights from now on. The thing is with the Scully episodes is that they're just so unfocused, but there's plenty of funny lines. That's in his defense. And I enjoy some of the wackiness.

Favourites: Lard of the Dance, D'oh-in In The Wind, Lisa Gets an A, Wild Barts Can't Be Broken, They Saved Lisa's Brain, Thirty Minutes over Tokyo.
Least Favourites: When You Dish Upon a Star, Homer Simpson in Kidney Trouble, Viva Ned Flanders, Monty Can't Buy Me Love

Season 11: Even more wacky than before, and one of the least popular seasons in the series. I can see why, but I strangely enjoy some of the antics here. I even find some enjoyment from one of the least popular episodes in the entire series: Kill the Alligator and Run.

Favourites: Brother's Little Helper, Grift of the Magi, Pygmoelian, Last Tap Dance in Springfield, Behind the Laughter
Least Favourites: The Mansion Family, Saddlesore Galactica, Alone Again, Natura-Diddly, Bart to the Future, It's A Mad Mad Mad Mad Mad Marge.

Season 12: The show for me starts to get this certain feel. It doesn't really feel like the Simpsons anymore, for reasons I can't really explain. This is the final year of the reviled Scully episodes.

Favourites: Lisa the Treehugger, Worst Episode Ever, New Kids on the Blecch (guilty pleasure ), Hungry Hungry Homer, Bye Bye Nerdie, Trilogy of Error.
Least Favourites: Homer vs Dignity, Tennis the Menace, Simpsons Safari

Season 13: We get a new show-runner, who hasn't been replaced as of yet. Fans saw this as a sign that things would improve, IMO they have, slightly.

Favourites:

Oh whatever I'll edit this later

Simpsons Roasting on an Open Fire, I thought was quite good. I'm not a Simpsons geek like Skyline, so I can't name many specific episodes, but this does stand out as one of my favourites from many years of watching.

The Halloween ones were quite good too

Favourite: 'Attack of the 50ft eyesores' from the 'Treehouse of horror' series (I wish i could find it on DVD). I liked the giant mascot monsters, it was kinda creepy but cool


Least favourite: Forgot the title but the one where they had to come to Australia, so Bart could apologize to the Australian people over that silly phone-call regarding the way our toilets flush. I hated it with a passion, because it was so lame, stereotypical and made a mockery of our Australian culture, especially Homer bragging about how America is so awesome and #1 at the end when they headed home!

In fact, came someone name a non-Australian cartoons that doesn't portray us Australians as being rough, living in shacks in the desert, using kangaroos for transport, wearing cowboy style outfits and hats, and overusing the word 'crikey'? For bonus points, try finding an Australian character that isn't stereotypically Australian and has an actual Australian actor doing their voice rather than some American putting on an exaggerated 'Crikey' accent (Believe me, we sound NOTHING like that! )