Hod off a minut4e if you are reading.
Anpther thread the person fixed this by disabling third party browser extensions. Even if not spyware, they can go corrupt.
Download and save this reg file and then double click on it, say yes to the prompt.
Here's the link to the regfile.
http://windowsxp.mvps.org/reg/DisableIEExtensions.reg
Restart and see if the problem is now gone please.
(Yuo can try to start explorer manually first. I am not sure it is really necessary to restart. But if no explorer, please try the restart)