I was having problems with Opera and Flash.
Played around with it with a variety of fixes, and it was still buggy.
Then Friday (5 September) Opera came out with 9.60 BETA RC1 - http://my.opera.com/desktopteam/blog/20 ... -beta-1-rc
This contains the following: UNIX: Additional fixes to flash plugin handling. Freezes when using flash should now be mostly gone.
Installed and running fine, so far no problems with YouTube or other flash related sites.