Are you using the windows key on your keyboard (the funny key between the Ctrl and the Alt key with the windows icon it)? Using it by itself will open the start menu. Using it and the letter D – will take you back to your desktop. Using it and the letter E – will open a windows explorer screen. These seem to work in all the versions of Windows but there are lots more of these shortcuts for the different Windows operating systems, which you can find in Wikipedia when you search for windows key.