With Kubrick, I always enjoy discussing his films more than watching them. The pace of them is very different to today's films.
A clcokwork orange I enjoyed a lot as a movie, but I found the social comment it was making far more interesting, and that's why I would rate it in my top 20 movies, since the message supercedes the film. Equally I loved Full Metal Jacket.
But Kubrick nailed it with 2001: A space odyssey. Neither before or since has a film ever captured the feel of space like that film. The use of lighting and sound in that film was just perfect....space is a silent, empty void - not that you'd know it with films like armaggeddon and even Apollo 13. Brilliant, brilliant film.
In case you couldn't tell, I LOVE kubrick films!