Ken;
Reboot tapping F8 each second.
Select Safe Mode at the menu.
Select Administrator.
Then go to User Accounts in Control Panel.
You can create a new account with Administrator access.
And/or select a user.
From there you can Change Account Type to Administrator.
Password all accounts with Administrator access including the default
Administrator.
Give all other users access only to Limited profiles.
You must tightly control all Administrators because Any Administrator
can do and undo anything any Administrator can do.
Take appropriate precautions to prevent losing the passwords.
You should use an Administrator profile for Administrator work.
Use a Limited profile for all routine work.