Disable Windows 7 UAC

In Windows 7 or Vista, the screen is dark when the User Account Control window appears, which is extremely annoying. They call it the "Secure Desktop", but I think it's disgusting.

Note that because your system is less secure before proceeding.

Windows 7 makes it easy

if you are 7 with Windows, you can simply read the UAC settings in the Control Panel (or type UAC into the search box), and head and drag the slider down until you see "Do not dim the desktop".

This is all done!
Windows Vista Business / Ultimate users
to the configuration screen, type in security to the start menu search box. You should see the Local Security Policy as a top search term.

In the Local Security Policy window, navigate to Local Policies \ Security Options

Scroll over the right part of the window, down near the bottom and find the article titled "User Account Control: Switch to the secure desktop when prompting for elevation". Then double-click to open it, and then change it to disabled:

Is to be disabled at this point Secure Desktop.
Windows Vista Home Users
for Windows Home users, you need to open regedit in the Start menu search box. Browse this registry key:
[HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Windows \ CurrentVersion \ Policies \ System]
In the right pane, right-click and set a new 32-bit DWORD value named PromptOnSecureDesktop by setting the value to 0.
Downloadable Registry Tweak
Just download, unzip and double-click the file DisableSecureDesktop.reg to the information in the Registry. There is also an included file EnableSecureDesktop.reg, to put things back in order, as they were safety concerns.

You can see by the large number of comments that this article is disputed. It is true, disable security features will always make your system less secure, and you may want to consider the consequences before you make any changes like this.