If you have forgotten the Windows XP administrator password, try the following:
1.First reboot Windows XP in safe mode by re-starting the computer and pressing F8 repeated as the computer starts up.
2.Then (in safe mode) click Start and then click Run. In the open box type “control userpasswords2″ without the quotes.
3.You will now have access to all the user accounts, including the administrators account and will be able to reset the lost password.
4.Just click the administrators user account, and then click Reset Password.
5.You will need to add a new password in the New password and the Confirm new password boxes, and confirm by clicking OK.
All done, this is how you recover an admin password.
There could be many different scenerios in lost password case, so be sure to search for the right solution online.