Hm... well, it's brand new, but School of Rock is cool. Although I imagine it's probably not as much fun if you don't like Tenacious D.
As for some older films, what everyone else said, plus...
Casablanca
The Big Sleep
The Maltese Falcon (only saw like 30 mins of that
but it seemed very good)
As good as it gets
Les Visiteurs
Groundhog Day
Back to the Future trilogy
The Good, the Bad and the Ugly
The gods must be crazy (both 1 & 2)
Ocean's Eleven
