There's little question that "Star Wars: Revenge of the Sith" was the best of the prequels. I wouldn't go so far as to call it a great movie, but it does have its moments.
One in particular that I'm thinking of - and was lucky enough to see last night, having flipped to the channel just in time - was that moment when Anakin and Padme are "looking" at each other from across the city, and Anakin is slowly sliding into the dark side of the force and Padme can seemingly sense that it is happening. It's a great cinematic moment, and it sticks out like a sore thumb in this movie because it is quiet. For once, Lucas (who really seems to have forgotten how to work with actors) keeps things quiet, and just lets the visual on the screen tell the story.
And then Threepio walks into the frame, there's a quick cut to Obi-Wan fighting General Grievous, and it's over. Cue the loud sound effects.