The Active Desktop accessible via Start/Settings can be disabled. This Windows NT registry hack disables access via Explorer but does not disable the same functionality accessible by right-clicking the desktop. Cut and paste the following script into noactive.reg file and run it.

REGEDIT4
BLANK LINE GOES HERE
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer] "NoSetActiveDesktop"=dword:40
BLANK LINE GOES HERE

See .REG files for background information on .REG files.

The following tweak prevents disabling via desktop properties:

REGEDIT4
BLANK LINE GOES HERE
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer] "ForceActiveDesktopOn"=dword:1
BLANK LINE GOES HERE

Other active desktop values installed via IE, include :

• NoFavoritesMenu : Removes the Favorites folder from the Start menu
• NoFolderOptions : Removes the Folder Options menu item from the Settings menu
• NoRecentDocsHistory : Removes Documents History
• NoRecentDocsMenu : Removes the Documents command from the Start menu

IE installs the Windows Desktop Update component. See How to Add or Remove Windows Desktop Update for more information including the Active Desktop component.