I did an update on computer 10.6.8 today and now I have spent hours trying to figure out why You Tube screens are just a black screen with no play options etc

Im not the most Computer tech savvy fella, stopped doing updates along time ago as I always have issues after updates. Thought I'd do one and sure enough here I am with issues. At First there was aplug in error > I uninstalled and re-installed and that has now gone buy all i get now is a black screen on You Tube that should have options to play but these options are not there. Any help greatly appreciated