Hocus Pocus and The Nightmare Before Christmas ooze holiday spirit, but Trick 'r Treat is prime Halloween essence if you're keen on the truly horrific. I also like to try to watch a new horror movie each year at the time if I can as sort of a Halloween tradition.
Whenever Halloween rolls around I rewatch slasher films. Things like Friday the 13th or Halloween (It's in the name of course LOL) They've always been the spirit of the holiday to me, even if they aren't set around the time. My guilty pleasure is Freddy vs Jason; it's more campy than creepy in my opinion but it's so fun to watch. I love camp.