Log In to a Standard-User Account
If you really can't stand UAC, consider logging in to your system using a nonadministrator account. The less privileged the profile you use to log in, the more secure your PC will be.
One way to demote an existing account is to use the Local Users and Groups administrative tool (lusrmgr.msc) as explained in tip 19 of "76 Ways to Get More Out of Windows." Vista Home and Vista Home Premium lack this tool; so if you're running one of them, click Start, type User Accounts, and choose that item from the search results. Make sure that your system has at least one administrator account you can log into. Select Manage another account to demote a profile other than the one you're currently logged into. Confirm the command when UAC prompts you to do so. Select the administrator account that you want to demote, click Change the account type, select Standard user, and choose Change Account Type (see the image below).
For safer computing, demote an extra account to the level of a standard user and log in there whenever you plan to do general-purpose work on your Vista PC. Because you'll be working as a less-privileged computer user, you weon't be able to do things that trigger UAC's interest (and interference).
From now on, use this less-privileged account for your daily computing. When you need to install or run an application as an administrator, right-click its .exe file or shortcut and choose Run as administrator. This command won't be on the context menu for shortcuts pinned to the main Start menu, but if you click All programs and right-click its shortcut there, you'll see the command. After you select it, you'll be prompted for the account name and password under which to run the program.
You can also combine this tip and the next one for occasions when you need to run several apps as an administrator without logging out of your limited account.