Just finished up my series on Star Wars movie novelizations for About.com. (There are a great many more adaptations of the six Star Wars films, of course, but one thing at a time.) Here they are, in order from worst to best:
6. Episode V: The Empire Strikes Back by Donald F. Glut is just... pointless. There were too many changes made between the screenplay used for the novelization and the final movie -- in particular, the dialogue between Han and Leia -- and the novelization adds nothing that wasn't in the movie. Possibly worth reading before ESB came out on home video, but certainly not now. 1.5/5 stars.
5. Episode II: Attack of the Clones by R.A. Salvatore definitely tries, including a lot of additional material that wasn't in the movies. Most of it is dull, however, and makes the novelization drag. If you want the extra material, watch the deleted scenes on your AotC DVD, but don't bother with the novelization. 2.5/5 stars.
4. Episode I: The Phantom Menace by Terry Brooks gains half a star just for the opening scenes with Anakin and the way it develops his character beyond what's possible on screen. The rest of the novelization is just average, however, and the poor action scenes drag down the ending. 3.5/5 stars.
3. Episode IV: A New Hope by Alan Dean Foster is definitely the best novelization, stylistically, of the Original Trilogy, and it does a good job integrating background information to develop the universe. On the other hand, it fails to develop Darth Vader as a serious and frightening villain, which damages the story considerably. 3.5/5 stars.
2. Episode VI: Return of the Jedi by James Kahn has a lot of stylistic problems, including glossing over a lot of the action (a major fault of movie novelizations as a whole). However, this is redeemed by the added scenes and the way the the novelization gets inside Darth Vader's head, making the final showdown between Vader, Luke, and Palpatine a lot more involved and interesting. 4/5 stars.
1. Episode III: Revenge of the Sith by Matthew Stover is the best movie novelization I've read so far, hands down, especially considering the mess of a movie it had to work from. The dialogue feels natural, the characters and their relationships are much better developed, the fight scenes are kickass, and the book really reads like a novel, not like a novelization. If you only read one Star Wars movie novelization, it should be this one. 5/5 stars.
Interesting that the weakest movie in each trilogy (in my opinion) produced the best novelization. Although I suppose that makes a bit of sense: if you've already got a good movie, there's not a lot the novelization can add and a whole lot it can take away; whereas with something like Episode III, there's nowhere to go but up.