Subtle is the operative word here

Rating: 10/10 (13 July 2001)

I am 23 years old. I have never seen 2001: a space odyssey in the theater. I was not there in the 1960's to experience that time and place. Nevertheless, this film stands out to me as the greatest film ever made.

After I first saw it, I did not get it. So like every other supposedly `great' films I didn't understand after the first time (Andrei Rublev and Vertigo also come to mind), I RESERVED JUDGEMENT because I knew that people who were more intelligent than myself had found real meaning in it. I did not dismiss it as so many others who have chimed in with their pedestrian comments here. After the second time, it made a whole lot more sense. Over time, it has become my favorite.
I will not attempt to explain what is going on with the monoliths and the embryo in outer space and whatnot. I have a very definite idea about what they mean, but I sorely regret having gone to the Internet to read about the meaning of this film rather than discovering it for myself. That's the whole fun! It's sitting back in your chair as this film fully engrosses you and as you catch one of the very subtle queues you say to yourself, `Stanley, you magnificent b**tard!' But I will give you one hint: like all other Kubricks, 2001 is about what makes us human. Look at the evolutionary changes in humanity throughout the film and what has precipitated them- that is why Kubrick made it.
Even so, after seeing it over and over and loving it more and more, I held the view, as so many have espoused here, that 2001 is too slow. Like every other criticism I have ever had of a Kubrick film, I was wrong. Indeed, the pacing is one of the qualities that makes it great. The complaint that the sequences could be done in less time is true, but that's not how real time moves. This is a film about evolution. It is not fast. Space walks are not completed in 20 seconds. Kubrick intention in these scenes is twofold: one a realistic expression of what it is like to be an astronaut. Two, to present the idea that we are like fish out of water in space; that inorganic life is better suited for the vast expanses of space.
It has been said that the dialogue is boring. It's meant to be that way! Kubrick's saying something about the dehumanizing effect of culture and technology. (Geez, I promised I would not discuss the film, but some of the criticism really irks me.) Indeed, Stanley's work is not accessible to most of the public because it is subtle. If mass audiences are to be given any sort of message in a film, it almost needs to be Spielberg style. They need to be hit over the head with it.
It is not necessary to see 2001 on the big screen in order to appreciate it. I never have and it is my absolute favorite. I will grant that it should probably be much better, but that should not stop you from watching it. Just make sure to get the widescreen version. (BTW, the new remastered Kubrick Collection DVD is great.)
2001 is a wonderful film that stands on its own two legs. It does not need to be explained by the book or any other source. All you need to know about 2001 is right there on the screen in front of you.