You know... I just don't get this attitude that these shows are not viewable at HD resolutions. I own a 720p set and both an HD-DVD player (HD-A3) and the Sony Playstation 3. These shows look fine when upscaled to the 720p resolution over HDMI.
But that's the thing: When you watch TNG (or DS9 or Voyager) like that, you aren't actually viewing the show *in native HD*. Just upconverted standard-def programming. There is a difference. Upconversion does not mean HD.
Take your 720p set, for example, and watch a TV channel that is standard def, i.e. not HD. You are still watching something that's upconverted (if it wasn't, it'd be in a little box in the middle of the screen surrounded by black).
This is why 'upconverting DVD players' are a bullshit marketing gimmick. ALL HDTVs upconvert (for exactly the reason I just gave). And most of them have upscalers that are better than any upconverting DVD player could hope to have.