Look for something on bootup that talks about system recovery, usually it will be F2 or something like that. If that does not help, hit f8 as it tries to start and it may give an option in the menu that comes up. Other option, if you know someone who has a vista non branded oem disc, you should be able to reinstall using the disc and the liscense number on the bottom of your computer. But do not use the number on their cd case.