I love Treehouse of Horror episodes. The one time in a season, when rules and continuity don't matter. Quite frankly, I like to be scared.
Now to the episode..
So far, this is the only episode actually set in a tree-house.
The animation is surprisingly flawless for a season 2 episode..
"Bad Dream House" was awesome, although slightly shocking for a Simpson's episode..(but it's nothing compared to later eps..).
"Hungry are the Damned" was far above average.
The whole "How to cook for Humans/How to cook forty Humans/How to cook for forty Humans" was absolutely classic.
"The Raven" was slightly below average. I know it's a poem/story, but it isn't very scary.
An above average episode.