BTTF FTW.
Both movies are definitely nostalgic favorites, but Back to the Future was the ultimate teenage fantasy when I first saw it in the theater. I don't think I ever saw the sequels.
Also, I've never seen a message board poll that lasted for 2 years before. Kudos.
P.S. A guy in my office sometimes drives his DeLorean to work. He told me he seriously considered tricking it out Emmett Brown-style, but decided against it since he actually uses the car for transportation.