Click the
Start button then
Control Panel, double click
Add or Remove programs, search for any IE add-ons you have installed like Google Bar etc and un-install them. See if that helps.
One more thing you can try - try logging into different user account, see if IE works there, if it does then launch Internet Explorer and use Google to search for more possible solutions.
It is also a good idea to
run a complete virus scan just to be on the safe side.