Having sadly having seen all the films and read all the books it's all a bit mundane to me now :)
I really recommend the original book (get one which includes the original couple of short stories the story is based on, one is called The Sentinel). But ignore all the sequals (film and book) they just steal the magic away from it.
In the movie Bowman becomes the 'star baby' some enigmatic uber-consciousness by travelling through the jupiter monolith. Best just to leave it at that really, it's open enough to read into it what you want.
I.e. anything the creators claim it to mean has probably been thought of later. But the machine does seem to take humans onto their next stage of development twice, once with the monkey men and again with Bowman. Who knows what this mysterious force has... etc.
I still love it. I remember the first time I ever got through it all at about the age of 14. As a kid I was gutted there were no laser battles and used to turn it off.
Book Spoilers (though they are shite really).
In the further books we realise it's basically just some poxy machine created by some poxy beings that I can't even remember if they turn up at the end. At this point it seems to be getting confused with Start Trek IV in my head.
In 2010 the monolith proliferates acros jupitor and turns it into a sun so some Jupiterian creepy crawlies can become senitent in just seven days (or your money back).
In 2061 a copy of Bowmans consciounsess becomes a part of the monolith, as does Hals. Oh and the bugger about on Haley's comet as well.
By 3001 it's all people flying dragons and cranial implants to advance humanity and Poole comes back from deep space.
I heard Clarke didn't actually write any of the sequals himself, though I'm sure he had his ideas in there.
