Oooooo yes nice topic
Definately the opening shot to Clockwork Orange, as Clipper said. Those eyes, that synthesised Ludwig Van.......
And another vote for Sellers on the phone with Dmitri

Yes, I'm happy, you're happy ... yes ... yes it's good to be happy ... yeesss
The Shining: Little Torrence on his bike ... bbrrrrrrrr KLANgggggg brrrrr KLANgggg then suddenly stopping and staring at the sisters

Then I love the opening as well (even with the shadow of the chopper in clear view!! How unKubrick is that

)
2001: All of them

'specially the last shot.
Lolita: Lolita saying goodbye to Mason as she leaves for summer camp.
Eyes Wide Shut: The pot smoking scene where it all starts to go horribly wrong. And I quite like the scene round the pool table as well.