The Ultimate Edition CD is absolutely the best star wars music i have ever heard. Finally being able to hear the entire movie score (with a few extra songs!) is a real treat, and i really hope they do the same type of CD for episodes II and III. The best song on the whole soundtrack, in my opinion, is easily "Anakin is Free", with it's combination of various instruments, themes, and just plain gorgeous music. Also, being able to hear the entire battle sequence is great, and the funeral song from the end of the movie is really awesome (if you haven't heard it before without the people talking in the movie, you're really missing out :)).
John Williams has created another keeper with the Episode I score, and I have not, for one moment, regretted buying it. It's worth the money, as you can listen to it over and over and never tire of it, mostly because there's just so much THERE! Either CD is great to listen to anytime, and listening to the whole soundtrack (both CDs) all the way through is a lot of fun :).
The best thing (besides the music itself of course) about this CD is the way that the songs are split up, so if you just want to listen to a piece of a song, it's easy to find, and likely already its own song. However, if listened to straight through, the songs move seamlessly along, with teh exception of songs that are seperated in the movie.
This is definately a CD i recommend to anyone, whether they normally listen to classical music or not, since it's so beautiful and has that movie music quality which makes every note impactful.