The one program I did not install when I followed your "Perfect Desktop fro Ubuntu" (might not be the exact name, sorry) was Opera. I felt satisfied with Firefox (from past experience.) Well, I went back and installed Opera and flash player does not work properly, there, either. Then tried Firefox 3.5 and the same.
During an update (a few minutes ago) I discovered that Sun-Java has an error.
E: sun-java6-doc: subprocess post-installation script returned error exit status 1
Could this be a Java issue? I am concerned that I am not experienced enough to be able to do some of the suggestions I saw when I Google this error message.