I'll go with a movie that had an awesome opening, but was actually pretty bad, since most of the movies you guys listed were cool the whole way through

...swordfish

The Lord of the Rings: The Fellowship of the Ring

After that probably the Two Towers, Saving Private Ryan, the Matrix, and a few others.

Spoiler alert: here's the first 6 minutes of the Dark Knight (in really crappy bootleg form).

http://www.youtube.com/watch?v=dc3EkaHiGDU

For opening scenes one of the most memorable for me was Scary Movie 2. That was when they took the piss out of The Exorcist. The possesed girl made some offensive remark to the preist and he just pulls out a hand gun and blows her head off (ha ha ha!).

 That was the first thing that came to my mind as well.

 I also agree that the original Star Wars has a great opening scene.

Blade Runner came to mind, its a pretty cool beginning....

For full on action beginnings... i would have to go for Transformers! Now that was intense! :P

SW IV, Indy and Ryan of course

X-Men 2 : the Nightcrawler run inside the White House. First time that, at the end of a scene, I actually heard all the audience taking a breath because they've been holding it until then.

Matrix : before the movie come to France, a US friend of mine send me a link to the "trinity beating up cops" opening scene. Whoa.

Chasing Amy: Jason Lee is gold in the opening scene. This film has the best opening 10 minutes of any film ive seen.