Well the story ain't bad either, but bingo, Kubrick is like an play/painting (I always think of Vermeer) that lasts 2 hours, has a great score, and if you're really interested, a story. There are also a lot of parallels with music in his work - e.g. the way themes are repeated (bone -> spaceship: pod out -> Bowman in: apes on Earth -> men on Moon: etc.) It's art of the highest class.

Some of the images in 2k still startle me with their sheer audacity. The opening sequence is clearly 100s of millions of years in scope - every time the frame changes, click off another 25 million years. This entire opening up to the space cruiser still gives me goosebumps. You have to see it in 70mm at a quality theater.