Which is the reason DRM and the like is hurting these companies - you paid for the movie or tv show and you can't watch it at home on your media center computer. The box doesn't say "stand alone DVD player required" or "These disks will not play on a Media Center computer DVD drive" does it? I didn't think so (example is the recently released "Daria The Complete TV Show". My media center won't play it from the dvd drive because of copy protection. I don't own a stand alone DVD player, so without ripping it or backing it up my wife cannot watch her new disks. One I get some free time, the media center will be replaced with MythTV.
So, act responsibly, buy the movie, tv show, or game and you can't watch or play without circumventing the DRM. Great business model - you got my money and I got something I can't view. Too bad the U.S. doesn't have the product law Britain does, I might have some recourse.