Please see the 4-5-1-2-3-6 discussion here. It is the order I recommend for reasons there discussed. My ideas were well received by other posters to the thread.

I believe that 4-5-1-2-3-6 is clearly superior to 4-5-6-1-2-3 and very far superior to 1-2-3-4-5-6. Depending on how you feel about the PT, the best order is either 4-5-1-2-3-6 or 4-5-6-done.

As for which versions, [strike:I recommend Revisited for ANH, GOU for ESB, ADigitalMan’s edits for the PT, and GOUT for ROTJ.] I recommend Revisited for ANH and ADigitalMan’s edits for the PT. For ESB and ROTJ, see ChainsawAsh’s post immediately below this one.

[strike:If the non-anamorphic GOUT looks bad on your system, you might want to see if you can find OCPmovie’s Classic Editions. From what I understand they’re better-quality versions of the GOUT. I don’t know whether they’re still available. I don’t have them and there are no links to them in the usual places.]

EDIT #1: Incorporated ChainsawAsh’s recommendations regarding ESB and ROTJ versions.

EDIT #2: I can’t get strikethrough to work. Is there a trick?