I am running Vista Home Premium. Not 100% sure, it came preloaded with Dell. I am playing a DVD, "Dexter" by Showtime. the screen breaks up displaying multi-colours intermingled with the movie. The sound is OK. I rented two movies. The first movie played fine (StepBrothers-Will Ferrell-funny). I put in the second movie, (Dexter/ by Showtime). The second movie plays, and the sound is working fine, but once the picture comes on, the screen breaks up displaying mulitple colors and lines. It's like how the screen breaks up on my digital tv, when a storm is coming in and it looses its signal, without the audio garble though. I have a Dell desktop, Inspiron 531, 2G. Any suggestions? Thanks