A. Windows Vista is very different from Windows XP. Under XP, the local users you create during installation through the setup wizard are all designated local administrators. They acquire a lot of privileges, so don't allow a lot of administrators. In Windows Vista, the built-in Administrator account is disabled by default, and only the first user created through the setup wizard is made an administrator. Any other accounts created through the setup wizard are only normal user accounts.
You can upgrade user accounts to administrator accounts through the User Accounts Control Panel applet.