ERRORS FOR ALL MEDIA & MEDIA PLAYERS

I just recently screwed up. I don’t know what I did but it is REAL bad. I have an R-Series Vaio with Media Center. I cannot access media center anymore or any other kind of media file....it doesnt matter what player i use or what file i open...its almost like i screwed up my video card or something. Anyway, I am an animation student and these players and files are vital to me. I NEED HELP!!!!!