If you like philisophical movies, Donnie Darko is awesome.

For plot twists, Fight Club is good (Action) as is Signs (Suspense)

If you're into animated movies, you might like The Incredibles. One of the few animated movies I truly like.

And of course, comedies, try Airplane, it's awesome. Monty Python's good if you're the type who'd get into it. I'm also a fan of the Scary Movie series myself (Especially 3)