|You understand what "format" means, right? The hard drive will be wiped clean & all data will be lost. You will then need to reinstall Windows, the device drivers, run Windows Update, then reinstall all your programs.|
BTW, why do you want to format?
You don't need a password to format. Just boot off the Windows disc & follow the instructions. Do you have an OEM system (Acer, Dell, HP, etc)? If you do, did you ever create the recovery disc set? What's the make/model of your system?