Puter being odd

[Knipples]

The last few days whenever I try and watch a video on you tube, or on the BBC site or anywhere else that shows videos I just get a blank screen. The text is there, but where the video should be is just a white bit of screen.
Like this


and heres the BBC site



Even photobucket isnt behaving in the way it should where the box usually is to click on to upload stuff.



Any ideas people, its getting a bit annoying now!