Drive no longer reading dvd movies

I have a Benq 1610 DVD RW. Recently I installed the game Silent Hunter 3, which uses the infamous Starforce copy protection $cheme. (SH3 is an excellent game, though). After this install, I find my drive will no longer read (enable me to view) movies on DVDs. Anyone ever heard of this? How do correct. Other than this, the drive is working fine.

OK, I tried a movie with Media Player Classic and it worked. But when I try to view movies with Windows Media Player 10 and Cyberlink PowerDVD, I get the same pilelated mess in the intros. Anybody know why this might be the case?