1. Luke v. Vader (VI): My favorite lightsaber battle. For me it was the most dramatic of all the battles, and it was cool to see Luke finally at his peak, his training complete. Plus, the black uniform and the glove were cool.
2. Sidious v. Yoda (III): I enjoyed this one so much because it involved two of my favorite characters and it was unexpected. I wish it had been a little longer though.
3. Maul v. Qui Gonn v. Obi Wan (I): Bar none, the best sequence in all of TPM, which is why I rank it so highly-most of the other SW movies had other action good scenes, but this is about the only one for me in TPM. It took forever for Maul to get down. It's really unfortunate that he died so quickly.
4. Luke v. Vader (V): The hand chopping, the revelation, what more can I really say.
5. Obi v. Anakin (III): The Duel was good on a technical level, but there was something detached about it. I wished that Obi had been pushed to his limits more, that there had been more emotion packed into that battle.
6. Dooku v. Yoda (II): It was great to see Yoda fight for the first time. I also liked the contrast of styles between him and Dooku. Though looking back at it, Yoda pretty much just jumped around.
7. Obi v. Vader (IV): It's not as fluid as later lightsaber battles, but the acting and dialogue more than make up for that. And Obi's end is still impactful.
8. Mace v. Sidious (III): I thought Sidious cleaved through the Jedi Masters far too easily, but his battle with Mace Windu had been a long time coming. I just wished it had been longer and we had been able to see a little more from Mace.
9. Dooku v. Obi v. Anakin (III): A nice evolution, or perhaps not so nice evolution of Anakin's temperment and skill in the second battle against Dooku.
10. Dooku v. Obi v. Anakin (II): I liked the two-handed lightsaber action, though it was far too short. Didn't like the day-glo closeups of Anakin. As for Dooku, I really liked his more elegant style and his curved lightsaber.