I don't think that will work, it would if it were a password on the BIOS but it's something with Windows.
Never been in that situation, you really shouldn't forget/never know the admin password unless it's some work computer the IT department is taking care of.
Try googling for things along the lines of reser / recover forgotten windows password. I'm pretty sure there are 3rd party tools to get around it as long as you have access to the computer.
If you have the windows setup disk, you can try the 3rd method listed here: http://www.askvg.com/how-to-reset-recover-forgotten-windows-nt-2000-xp-2003-administrator-password/







