Just to add, there's a lot of Lucasfilm BS about how the originals looked really bad and that's why they aren't available in any better quality than Laserdisc. This is quite simply a lie designed to peddle the Special Editions, nothing more.
In spite of being derived from some Special Edition sources, I feel that the Despecialized Editions more accurately represent the theatrical experience than anything else out there. If you watch anything based on the Laserdisc masters, they may be technically more accurate in detail (which I understand is important!), but they only represent the theatrical experience if you went to the theatre with some Saran Wrap wrapped around your head a couple of times. It just didn't look like that in theatres.