Or The One Where: "Bad Dream House" (the Simpsons move into a house possessed by an evil spirit), "Hungry are the Damned" (the Simpsons are taken into space by aliens) and "The Raven" (Lisa reads Edgar Allan Poe's famous poem to Bart).
The Setup: Before the opening sequence, Marge speaks directly to the audience, warning them that the show is scary, and that if they "have sensitive children, maybe you should tuck them into bed
early tonight instead of writing us angry letters tomorrow."
A Work In Progress: This is, of course, the first of the yearly Halloween specials. The framing device of this episode, in which Bart and Lisa swap scary stories in Bart's treehouse on Halloween, provides the inspiration for the titles of the subsequent specials, despite the fact that this framing sequence is unique to this episode.
The Halloween-themed opening featuring the camera zooming in over a graveyard with tombstones featuring humorous epitaphs is also used for the first time. The funny gravestone gag will be used in subsequent "Treehouse of Horror" episodes until it was dropped permanently after the fifth special (in the sixth season).
The tradition of opening each Halloween episode with a warning to parents and children begins in this episode; it will be used on and off throughout "Treehouse of Horror V", when it, like the tombstone gags, will be dropped because the writers found it too difficult to come up with new material for the gags each year.
Finally, Kang and Kodos, the green, one-eyed, squid-like aliens, appear for the first time. It is an unwritten rule that they must make an appearance in all Halloween episodes, and their presence is usually seen as an indicator that the events of an episode are non-canonical (they've appeared outside "Treehouse" episodes a few times).
Favorite Lines:
Homer: Mr. Bloot? Homer Simpson here. When you sold me this house, you forgot to
mention one little thing: YOU DIDN'T TELL ME IT WAS BUILT ON AN INDIAN BURIAL
GROUND! ... NO YOU DIDN'T! ... Well, that's not
MY recollection. ... Yeah? Well, all right, goodbye! ... He said he mentioned
it five or six times.
Kang: We offered you paradise. You would have experienced emotions
a hundred times greater than what you call love. And a thousand
times greater than what you call fun. You would have been treated
like gods and lived forever in beauty. But, now, because of your
distrustful nature, that can never be.
Marge: Mmmm...for a superior race, they really rub it in.
Bart: Lisa, that wasn't scary. Not even for a poem.
Lisa: Well it was written in 1845. Maybe people were easier to
scare back then.
Bart: Oh, yeah. Like when you look at 'Friday the 13th, Part 1'.
Pretty tame by today's standards.
Teebore's Take: Managing to pay tribute to while parodying "Outer Limits", "The Twilight Zone", "Alfred Hitchcock Presents" and Gothic American poetry, "The Simpsons" first Halloween episode sets the standard and raises the bar for all that follow. This episode is also another early example of how, in the second season, "The Simpsons" is showing it can do more than standard sitcom jokes and crude humor and foreshadows the close relationship the show will have, both in the Halloween episodes and regular episodes, with culture, pop and otherwise, in the years to come. The clearest example of this, my favorite of the three segments in this episode,"The Raven", manages to create an eerie and creepy "Halloween" mood even if it isn't, as Bart and Lisa suggest, all that scary. It's worth it just to hear James Earl Jones' rendition of the poem.
Classic:
A definite classic that sets the stage for some truly hilarious entries in the series.
Halloween:
Between the framing sequence and a clear effort to tell scary stories, this is one of the more Halloween-y "Treehouse" episodes.
Or the One Where: Lisa crushes on her substitute teacher while Bart runs for class president.
Or the One Where: Marge paints Mr. Burns in the nude.
Or the One Where: Grampa inherits $106,000 when his girlfriend dies.
Or The One Where: Bart takes Santa's Little Helper to obedience training classes.
Or the One Where: Homer meets his half brother Herb. 
Or the One Where: Principal Skinner dates Marge's sister Patty.
Or The One Where: Homer steals cable, much to Lisa's disappointment.
Or the One Where: Homer and Marge tell the story of how they met in high school and fell in love.
Or the One Where: Homer thinks he's dying after eating poisoned blow fish. 
Or The One Where: Homer hires Lionel Hutz and files a lawsuit against Mr. Burns after his boss accidentally hits Bart with his car.
Or the One Where: Bart attempts to jump Springfield Gorge on his skate board.
Or the One Where: Bart runs away on Thanksgiving
Or The One Where: Bart and Todd Flanders compete in a mini golf tourny. 
Or The One Where: "Bad Dream House" (the Simpsons move into a house possessed by an evil spirit), "Hungry are the Damned" (the Simpsons are taken into space by aliens) and "The Raven" (Lisa reads Edgar Allan Poe's famous poem to Bart).
