Has anybody got a green screen when trying to see a video? I do almost every time.

I have a Gateway i7 computer using Windows 8.  Everyting has worked great until last week.  Now every time I try to see a video such a You Tube videos all I get is solid green screen where the video should be.  I get the same thing trying to watch a video for a upcoming game.  I used to like the color green  -  not so much now.