User Access control was a new feature introduced in windows vista, but has become increasingly annoying due to extra security clicks on performing simple windows operations.
Microsoft has changed User Access control features a little bit in Windows 7, and now it is some what better than its previous version of windows vista. Windows 7 UAC has options to set the level of different alerts and notification, much similar of defining security in Internet Explorer.
Easiest method to disable or turn off alerts and notifications for UAC is to going to Control Panel in User Accounts and Family Safety -> User Accounts -> User Account Control Setting
Move the slider to "Never Notify" to turn off UAC alert and notifications, and then reboot the system.