ahoj,
mala som rovnaký problém, preinštalovala som celý komp - nepomohlo....

našla som niečo, čo pomohlo - Youtube, Dailymotion and other websites use Flash video technology, so I looked it up a little bit.

It seems the problem comes from hardware acceleration that Flash v10 uses (I didn't have the problem with v9)

So first, check if you can see the Flash animation (banner) without the system crashing at:
http://www.adobe.com/software/flash/about/

Don't worry, it's not a video, it shouldn't crash -- if it does, your problem is not the same as mine.

If it works without crashing, right-click on the Flash animation (banner) and uncheck "Enable hardware acceleration" from the Settings panel.

Then, go on Youtube and you should be able to see the videos without any problem

videá mi fungujú už bez problémov.