Lion freeze when browsing webpage
I purchased a new 27' iMac two months ago. I upgraded to Lion yesterday. Everything went well until today when I browsed a Chinese website (www.6park.com) using Safari, the computer freezed. I noticed the freezing happened when the webpage contains some pictures or videos (but it didn't always freeze when there are pictures or videos). I can move my cursor but the system had no responsive no matter where I clicked, or no matter which key I stroke. I had to do a hard reboot (using power button). But it will freeze again after some time. This is the website I regular visited for news and postings. I never had this problem in Snow Leopard.
Do you have any idea what can be the problem? Thanks a lot!
iMac, Mac OS X (10.7)