I participated in a DVD marathon last week ... luckily, I didn't have to buy the DVDs before I saw them. Every single person in the room (30+ in age) wailed at every change. I'm sorry ... but the lightsabers were always fine. The explosions were always fine. None of this stuff needed to be spiffed-up. The FX were groundbreaking in the day ... now they're standard CGI ... no better than what's seen in The Star Wars Kid videos.
And something else ... while the DVDs' film quality was crystal-clear, the first two movies didn't have the same look as Star Wars did when seen in a theater. The colors were sharpened beyond anything that was seen in the day ... it's not the same color composition anymore. Everyone looks like they're wearing orange makeup (which they probably were ... because such makeup was expected to fade out to a natural fleshtone on film).
Frankly, if Lucas has issues with his first three films ... then he should freakin' REMAKE THEM FROM SCRATCH. New actors; new everything. But leave the original films as-is. As far as I'm concerned, he's had his chance to make Star Wars films with every modern toy available ... they're the prequels, and I happen to hate them.