Some great mentions in this thread so far. Some personal faves off the top of my head:

The baptism scene from The Godfather in which Michael 'settles all family business' during the baptism of his nephew.

The scene from Apocalypse Now in which Captain Willard finally comes face to face with Colonel Kurz.

The scene from The Shining in which the boy first encounters the two little girls in the hallway. The lead up to the vision is really well done, imo.

>The meat grinder scene in Stalker
>the opening sequence of Nausicaa of the Valley of the Wind
>Roy Batty's "I've seen things" speech from Blade Runner
>The ending of Return of the King
>"Jupiter and Beyond the Infinite" from 2001: A Space Odyssey
>The first ten minutes of Up
>The ending of Toy Story 3
>The kick-ass opening song from Yor: Hunter from the Future
>The ending of Planet of the Apes (original)

I'll go so far as to say EVERY scene in The Godfather belongs in this thread.

Yeah, I was just going with my personal favorite, but you're right. The wedding, Luca Brazzi's death, the scene at the hospital where Michael saves his father, Sonny's assassination, etc. and so on. All fantastic.

Another favorite of mine, which I doubt anyone else would consider 'classic' in the traditional sense is the scene from the movie Slapshot in which the Hansen brothers take the ice for the first time. The mayhem of the immediate scene is a sports movie gem.

Close but no...the scene of the Hanson's covered in blood, standing at attention for the National Anthem...now that was magical! "I'm trying to listen to the fucking song!"

That's a hilarious scene. But I prefer the one I mentioned because it's a portent for all that follows in the movie. If Dunlap doesn't put them on the ice, there's really no movie to speak of afterwards. Make sense?

From Lord of the Rings:

Arwen - if you want him come and claim him.
When they first go into Lothlorien woods and
Legolas shooting arrows and mounting the horse.

- Sunshine - those solar shots
- Kill Bill - 'Your name is Buck. Right? And you came here to fuck. Right?'
- V for Vendetta - V's speech
- 300 - King vs Ambassador:

There are some classic scenes already here. For somewhat lighter fare, one of my favorite scenes from a movie was actually cut from the movie. The Meaning of Life from Pirate Radio (aka The Boat that Rocked) - which also cut some of the other best scenes from the movie (e.g. pirates).

Keeping with the Rock'n Roll theme: Almost Famous, Tiny Dancer.

Also, one of the classics of cinema: Sherif Ali arrives in Lawrence of Arabia

Nobody's Perfect - last scene from Some Like it Hot. Two other brilliant scenes are the final one and Orson Welles' monolog on the ferris wheel.

I think the Opening Scene from Swordfish was very good.

The swing scene from Ikiru is pretty iconic. It kills me every time I see it.

That being said, I just want to leave the ending of trainspotting here ("choose life"):
http://www.youtube.com/watch?v=t0D4ekTODuA

So why did I do it? I could offer a million answers - all false. The truth is that I'm a bad person. But, that's gonna change - I'm going to change. This is the last of that sort of thing. Now I'm cleaning up and I'm moving on, going straight and choosing life. I'm looking forward to it already. I'm gonna be just like you. The job, the family, the fucking big television. The washing machine, the car, the compact disc and electric tin opener, good health, low cholesterol, dental insurance, mortgage, starter home, leisure wear, luggage, three piece suite, DIY, game shows, junk food, children, walks in the park, nine to five, good at golf, washing the car, choice of sweaters, family Christmas, indexed pension, tax exemption, clearing gutters, getting by, looking ahead, the day you die.


EDIT: here's a scene from "Thing from Another World" (1951) I always remember:
http://www.youtube.com/watch?v=dGjJ8vfh5CI&t=3m10s
"Holy cat"
"hey...it's almost"
"yeah...almost a perfect..."
"it is"
"it's round"
"we finally got one"
"we found a flying saucer!"