If you manage a bunch of desktops (like I do), you always have one or two idiots that decide to fiddle. In this particular case, the Intel graphics driver updates force a context-menu in the right-click on the DESKTOP and this gives the kiddies the joys of rotating the screen and freaking out the other users who are none the wiser for it.
Thankfully, Intel has given us an option to remove this context-menu, even though I'd prefer it even more that they didn't default install the darned thing. Check out this page (or google for the title above) and you should find the REG file to update the registry and stop those kiddies from messing with your screens.