Unfortunately, there are way too many that I haven't seen yet.
1) Scott Pilgrim - The closest thing I've ever seen to the feel of a comic book being embodied on film. Love it unabashedly.
2) The Dark Knight - I know it has lots of problems. I know it's too long. I don't care. Such a great cast.
3) X2 - Seriously underrated. The opening with Nightcrawler is one of my favorite action scenes of recent memory.
4) Spider-Man 2 - Another film that just captured the feel of a comic book really well. Just got the character of Parker perfectly.
5) Iron Man - Basically instantly made you read every future Iron Man comic picturing Stark as RDJ. Such a perfect fit, and the movie just coasts on his charisma.
6) Hellboy 2 - Surprised this hasn't showed up on anyone's list yet, given the love for GDT around here. Just love how unique it feels in all the character design.
7) A History of Violence - It isn't my favorite just because it isn't really my cup of tea, but I won't deny it's really well done, and there are some great moments.
8) V for Vendetta - It isn't as good as the comic, but what is when it comes to Alan Moore? It's heavy-handed, but I enjoy it a lot anyway.
9) Batman Begins - I'm a Nolan fanboy, and I've got a soft spot for Ra's.
10) Batman (1966) - "Some days you just can't get rid of a bomb!"