A fantastic film, I watched it in the cinema when it first came out in 1981, got the DVD and there is a Tron FPS game for the PC which is actually very good (it has a light cycle section in there but I found the game overall to be very playable).
Tron was very unusual by something made by Disney in the sense people got "killed" in that film, a very rare move for Disney at the time. And did you know that only 7 minutes of CGI took up that film?
It does look all very ropey and very ragged at the ends when compared to today's CGI efforts but still a groundbreaking film in it's own right.
I really think a sequel should be made using today's CGI wizardy, no harm in Hollywood giving it a go.