Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb is my favorite movie. It's got great characters, including three played by the same actor, is well written with some very quotable lines, and the story is both absurd and believable (even now).
I'll be the first to admit that it's not for everybody, but if you're asking for movies to watch it's probably for you. With movies I always recommend going in knowing nothing.
I could quote the whole thing probably, but I'll spare you and just say that the way the Russian ambassador says "fresh fish" is weirdly seared into my brain.
My favorite movie is probably Bill and Ted's Excellent Adventure. It certainly isn't the best movie ever made by any stretch of the imagination, but something about the way the jokes are written land perfectly for me every time.
It's not for everybody, but I definitely quote it more than a reasonable person should.