Windows Media Player question (Can't watch video full screen)

So all of a sudden last night I loaded a video and it wouldn’t go to full screen. Thought maybe something was wrong with the video so I loaded the video I had just got done watching and it wouldn’t go full screen either. Then I thought maybe I didn’t have enough RAM to display it (512MB RAM, 32MB Video) so I closed several programs and it still didn’t work. Rebooted, no dice. Today it was working fine, but I have no idea why as I haven’t tweaked anything. Now it’s not working again. I’m running XP Pro and WMP 8 (not the beta one.)

Does anybody have any clue as to what might be going on? Thanks.

Does anybody have any ideas? Could I possibly be the only person on the SDMB that this has ever happened to?