I feel that, to answer this question, a range of sorts would be a better way to answer. These are ordered by the frequency I choose each version - #1 is most often, #2 is less, so on and so forth.
Star Wars
- Dark Jedi's GOUT V1 restoration, usually with the 1977 mono mix, occasionally with the 1985 stereo mix, and recently with Hairy_Hen's wonderful 1977 70mm 5.1 reconstruction. (I also cropped out the yellow subtitles in the letterboxing, and made my own SRT subs to replace them.)
- Adywan's "Revisited" NTSC DVD-9
- EditDroid DVD (if I ever want to see the '81 crawl, that is)
- Official widescreen 1997 SE VHS (second set, after they stopped calling it the SE)
The Empire Strikes Back
- Adywan's 1980 Theatrical restoration, either with Ady's 5.1 or Hairy_Hen's purist 5.1 mix.
- Dark Jedi's GOUT V1 with the 1993 stereo mix.
- ABC/Dark Jedi's "Imperial Edition" (isolated score w/black-and-white video)
- Adywan's 1997 AVCHD restoration
- Official widescreen 1997 SE VHS (second set, after they stopped calling it the SE)
Return of the Jedi
- Harmy's 1983 Theatrical restoration, with Hairy_Hen's purist 5.1 mix.
- Dark Jedi's GOUT V1 with the 1993 stereo mix
- Official widescreen 1997 SE VHS (second set, after they stopped calling it the SE)
The Phantom Menace
- Adywan's 1999 Theatrical restoration, with the laserdisc 5.1 mix
- Official widescreen 1999 theatrical cut VHS
Any other versions I pretty simply never watch. I refuse to ever put the 2004 DVDs in, I have no reason to ever put in the official GOUT discs when I have DJ's restorations, I never have any desire to watch Clones or Sith, and I never have any desire to watch the official DVD cut of Phantom.
I really only put the SE VHS tapes on the list to illustrate what I'm willing to watch before any of those things I just mentioned.