Do you have a Windows 7 rescue disk? Can you boot this from your CD/DVD drive? Alternatively, do you have a bootable USB key? If you have another computer (laptop) running Win7 with a burner, you can make a rescue disk. Go to Control Panel\System and Security\Backup and Restore and Create a System Repair Disk on the left of the panel. Then try to boot this from your CD. You may have to review your BIOS settings to make sure this is enabled.