Turn the computer on and when you see the machine logo start pressing F8 repeatedly until you get the advanced startup menu. Choose to boot into Safe Mode. Once you get to the desktop, use a restore point to go back to when the most recent restore point was saved.
Once you get the system back up and running, there will be an item under Start -> maintenance or under the Compaq menu to make a set or factory restore disks. It may be an item under the backup. You will probably need 3 blank DVDs for this process.