Thanks for the response guys. I have seen many of these but there are some new ones I'm definitely going to watch. And any genre is fine including animated and musicals.

Rear Window
Young Frankenstein
The Lion King

Sleepy Hollow

Star Wars 1-6
The Dark Knight

Kill Bill
Spirited Away
Hunchback of Notre Dam

Once Upon a Time in the West
A Very Long Engagement
The Good the Bad and the Ugly

Jurassic park!

Casablanca

Here are 13 of my current super favorites, but they shift around all the time. They're all pretty old or pretty recent. I skipped over the 70s and 80s because they're not that hard to discuss. You've got Coppola, Chinatown, Kubrick, Gilliam, Buckaroo Banzai, Death Wish 3, Evil Dead, the rise of indie film, and tons of shit. But here are 13 of my favorites before and after then.

8 1/2 by Fellini (1963).
Week-End by Godard (1967).
Un Chien Andalou by Buñuel (1929).*
Battleship Potemkin by Eisenstein (1925).*
Kikujiro no natsu by Kitano (1999).
Blue by Kieślowski (1993).
Citizen Kane by Welles (1941).
Happiness of the Katakuris by Miike (2001).
Forbidden Zone by Elfman (1980).
Children of Men by Cuarón (2006).
One Week by Keaton (1920).*
The Cabinet of Dr. Caligari (1920).*
Night of the Hunter by Laughton (1955).

* = it's in the public domain, so it's up on Google Video for free and totally mandatory if you want be a film freak.

Lion King, armageddon, aliens, blade, the matrix, star trek 2, die hard, return of the king