While reading this thread, I've started coming to the conclusion that Episode II sort of sits there between episodes I and III. Episode I is rather infamous, being the most disliked of the prequels by many (and I'm sure many would say it's the worst of the series), while Episode III is the best of the prequel trilogy.
I agree that if I had to choose a favorite, it would be Episode III. But that's despite all the problems it still has.
I will say that Ian McDiarmid is always brilliant and a lot of fun as the Emperor. And Ewan McGregor, I really do believe he could be the same character that Sir Alex Guiness played, which is a great accomplishment.
But they just can't save what I felt was a very confused storyline. I could see the bare bones of the idea, but it hadn't been developed previously and they were really just asking us to go along with it.
I think what really messed up the prequels was starting with Anakin as a child. There was too much of a disconnect between Anakin the child and Anakin the young adult so whatever character development they wanted to get across was just lost.
In the original movies, Anakin became Darth Vadar because he was seduced by the idea of power. It's straight forward, it's classic, it worked. It addressing the dark side of our human nature. The prequels had too many motivations that never really gelled together. Instead of addressing Anakin's dark side, they try to make it seem like he's is just being manipulated by Palpatine. But it just ends up making him seem incredibly stupid. Plus even when Anakin
is lusting for power he just comes across whiny and annoying. I never believed he could actually become Darth Vadar. And not because he's so nice and good, but because he's so incompetent! ; D