I have noticed that the screenshot you posted is actually
Google Chrome,
not Safari (as you have said above)...
This changes things a little bit because there are well known problems with Chrome for OS X...
Also found someone with similar problem (unfortunately no details and no solution):
http://www.google.com/support/forum/p/Chrome/thread?tid=34fb8fc5a8f4cfe2&hl=en
I would suggest trying different browser (i.e. Safari) for confirmation.
If you plan to stick with Chrome try resetting it to defaults/reinstalling
from scratch (personally I wouldn't touch Chrome with a barge pole).
Hope this helps...