Hi there, to enthersise on what broken89 has just stated, in normal mode, when you come to the welcome screen press ctrl + alt + del twice, type the user name Administrator, then click ok, this will then log you onto another account, now just follow these easy steps:
*Click Start
*Control Panel
*User Accounts
*Click your wifes username
*Then click change the password
*Type your new password
*Confirm it
*Set a reminder if you wish
*Logoff
*Logon to your wifes account with the new password
Its probably best to set a reminder this time

, If you have any problems lets us know
