This is the User Accounts Screen.

Windows XP has a guest account by default. Unfortunately, this invites people to log in to your PC that shouldn’t be there. And unlike Windows Vista or 7, there’s no User Account Control to prevent people from messing with your PC, even from Guest. There are going to be instances where you’ll want to disable Guest altogether, in order to have strict, password protected users at all times.

To disable the Guest Account completely in Windows XP:

1. Click Start.
2. Click Control Panel.
3. From the Pick a Category screen, click User Accounts.
4. Under Pick an Account to Change, click Guest.
5. Click Turn Off the Guest Account.

Now that the guest account has been deactivated, you can be sure that only administrators and registered users can log on to the computer.

Note that you must be logged on as an administrator to perform this task.

Click Turn Off the Guest Account to disable it.