This would really ruin the magic of it all, I think it's incredibly awesome the second half was made almost twenty years before the first half. The Star Wars movies get a lot of attention simply from their unique and different style of numbering and continuity that no other movie series has really come close to matching. To remake the originals would just kill that and make a lot of people lose faith in Lucas.
By the way, not entirely relevant, but even though I used to defend the special and DVD editions to no end, I prefer the originals greatly now. They're just less awkward and don't have this strange mix of animatronics and CGI the re-makes have. They look great on my high-definition TV (and this is talking about the ones on the official DVD), so I don't see why everybody's complaining about it so often.