Ever thought of doing it this way.
Disabling the local administrator account provides you with some added
security against hackers, and this account can easily be disabled in
Windows XP Professional.
"Before you disable the Administrator account, make sure that at least
one other account has administrator privileges. Now, log on as a member
of the Administrator group. Click Start and then right-click My
Computer and choose Manage. When the Computer Management window opens,
click the small plus (+) sign to the left of 'Local Users and Groups'.
Click the 'Users' folder to select it.