point5 said:

Thanks for explaining. I do still have some trouble understanding why some movies that were made much earlier than Star Wars do seem to have better quality DVD releases than Star Wars.

If you're talking about the blu-rays, it's simple. They used alot of digital tinkering to get dirt off etc, and in the process it smoothed over the whole film (I personally don't think it looks THAT bad)

The reason the original theathrical releases look so bad, is that they're made from laserdisk masters. So they weren't actually directly scanned in from film. It went scan -> digitial cleanup (Somewhat) -> laserdisk master tape -> dvd

Normally films are scanned in at 2k/4k and then downscaled to 1080p. Making them look much better.