Windows 7: One serious pain in the backside.

My friend has kind of messed her laptop up. She connected an external HDD up and it asked her if she wanted to do something with her programs she forgot what it said. She wanted to do no but of course the laptop buttons are useless and she caught yes. Now when she logs in windows media center starts up and everytime you x it it pops back up. Alot of her programs all start up with media center like internet explorer system restore turn of windows features. i cannot do anything to stop it. So i am here.

Boot into safe mode (F8), go to control panel, programs,l associate. find *.exe then change the associated program.