Whenever I try to play a video, windows media player (or other program) opens up normally but plays only the audio.  These are just simple .avi or .mpg files that were working yesterday.While viewing the thumbnails for these files in explorer, the first scene is shown as a thumbnail like normal.  My dvd viewing works fine.  I dont know if I installed something or corrupted something, but any help is mighty appreciated. 

-Tiburon

Unfortunately my knowledge of these sort of programmes is Zero.  But I will have rummage around to see what I can see