How does one rate quality? I go by use of surround sound and subwoofer (DTS, 5.1), visual quality (color, dynamics), effects quality (CGI, although that's more along the lines of movie, not DVD quality), and then there's my personal favorite- extras such as deleted scenes, easter eggs, making-of, out takes, etc...
I have way too many favorites, but some that come to mind (not counting those that have already been lsited)... Dune (director's cut), The Matrix, Ice Age, Blade 1&2, any of the Jurrasic Park flicks, Lord of the Rings, xXx, any James Bond movie.. too many to list.
I started a thread on another sub here about best DVDs to show off your home theater, be sure to check it out:
[Link: remotecentral.com]