Personal canon goes as follows:
Prologue - The Phantom Edit
- as good as the Phantom Edit was, this movie still doesn't seem to flow with the rest of the series. Basically, it's the SW version of The Hobbit.
Episode I - Attack of the Phantom
- I was stunned at how well this edit worked - in this incarnation, AOTC is perilously close to being a very good movie.
Episode II - The Clone Wars vol. 1 & 2
- easily the best things to result from the prequels, which of course have now been suppressed by Lucas. For personal canon purposes, chapters 12-16 have been removed from vol. 1, mainly for pacing. I feel really bad for Genndy Tartakovsky - this was some of his best work, and indicated what the prequel trilogy could have been if George was willing to collaborate like he did in the old days.
Episode III - Revenge of the Sith
- one of these days, I will make my own personal edit of the movie. Some of the fan edits have come close, but none have gotten it "just right" like the Phantom did. ADigitalMan's edit is the closest to my preferences, though I would take the cuts a little further, and hopefully I can find a way to rescue Vader's idiotic NNNNOOOOOO.
Episode IV - Star Wars
- for "saga" watching, I prefer Harmy's Despecialized edition. For "George Lucas Cinema" purposes (i.e. if one did a mini-marathon of THX 1138, American Graffiti and Star Wars), I prefer the Puggo Grande.
Episode V - The Empire Strikes Back
Episode VI - Return of the Jedi
- Harmy once again.
Episodes VII, VIII & IX - The Thrawn Trilogy