User Account Control (UAC) is supposed to be extra security, which was introduced with Vista and it supposed to fight programs being run without your knowledge that might harm your computer.

There is no middle settings, either the UAC is ON or OFF.  I turn mine OFF, but its a good feature for Novice Computer users.

You can find instructions on how to turn it off Here:

I recommend Method #4
http://www.petri.co.il/disable_uac_in_windows_vista.htm