Certain movies work, certain movies don't.
I've found Butterfly Effect to be great...
Requiem For A Dream doesn't make you happy, but it always puts me in a certain mood... the cinematography, the settings... the way they portray the addictions over and over again... incredible.
If you're in a humorous mood, Zoolander becomes one of the funniest things you've ever seen. I always find it boring and exaggerated when I'm sober, but stoned... man is it funny as HELL>
Half Baked is funny too, but it degrades (for me) after the first half.
People say family guy and simpsons and all that are great stoned, but I don't really go for that... too much witty humor that passes me by in my semi-slow state of mind.
Spiderman movies can be pretty fun to watch stoned... kinda rushy when he's soaring between buildings and such..
Final Fantasy Advent Children is beautiful...
Boondock Saints is sort of an underground movie, I had no idea it existed until a couple months ago, it's GReeaattt.
And if you like their accents, try Lock Stock And Two Smoking Barrels... another good one, semi-pot related...
The Beach is wonderful stoned, reminds me immensely of my dreams...
Waynes' World movies I have yet to try, going to this weekend, same with SLC Punk, hopefully very good..
OH! And "Hook"!! nice vibes stoned...
man I wish we could all plan a nice little get together at someone's house in L.A. or somethin... "Pass the popcorn, pass the bong, pass the drunken donkey, turn on the vid, get yur own bean bag chair... etc.. heh