|do you remember the password for the admin account ? If yes then |
press ctrl+ ALT+DEL at the login screen . You will see a login box .
Provide the username and password for administrator account. Hopefully you should able to get in. Then go and make changes you want..
Otherway to get in is safe mode..In safe mode you will see all accounts..
I think windows XP hides administrator account from logon screen once you have created extra users.. (there is a registry hack to enable it but i wont recommend here until needed..)