I think those ’92 covers are probably the best.

I’ve got a soft spot for the Special Edition covers as well. Having the covers on display in my office, I’ve been noticing how many elements are borrowed from the other movies, some of which have already been mentioned:

ANH:
I don’t think Leia had that hairstyle in ANH. (crissrudd mentioned this).

ESB:
Vader’s TIE is on the cover despite only being in ANH.
As Chaotic mentioned, the RotJ Emperor.
Vader is from a RotJ publicity photo.

Rotj:
Duel is from ESB
Boba Fett is from ESB?