Mad Fleas

I've just installed Internet Explorer 8, and after rebooting, Windows Explorer won't run. After I get past the welcome screen, it gives the message "Windows Explorer has encountered a problem and needs to close..." I tried to open Windows Explorer via the Task manager, but it's still giving the same message. (I'm now working in safe mode) Is it a registry issue? If so, how do I repair it? Should I try uninstalling IE8 to see if it will help?