Unfortunately, most of the best bits in the movie aren't in the book. The first one I think of is the sequence where Bowman has finally arrived at Jupiter. In the book, it's Saturn, and the Monolith is in the moon Iapetus; this is clever, and from a scientific point of view a more plausible place to put it, but poetically is completely flat.

In the movie, we get this unforgettable picture of all the Jovian satellites majestically lining up to the strains of Thus Spake Zarathustra; every time I hear someone use the expression "get your ducks in a row", my mind flashes a mental image of this scene, but with ducks instead of moons. I'm sure that proves something, though I must admit I'm not quite sure what.