This!
Try one or several to see what you like. Keep in mind though that the 2006 DVD is the master used for the 1993/1995 Laserdiscs so that has higher video quality.
As of now, the Dark Jedi GOUT V3 is the most complete and best looking version of the Original Trilogy that does not use any new footage as a source. (By new I mean 2004 transfers and later.) They also include multiple soundtrack options, if you have a preference for one mix over another.
Personally, I use that for ESB and ROTJ, but like the PuggoGrande (16mm transfer) and Technidisc LaserDisc transfer best for the original film as I like the more 70's era look they have.