Do a VBS or CMD on start up that will remove all access to the taskbar and start menu, modify windows boot and shut down screen (this can all be allot of work) then "Hide desktop". BTW If Windows comes out with an update you can lose your Boots screen and you will have to recopy over the files.
1. Right-click on your desktop.
2. Select Arrange Icons By.
3. You will see a Show Desktop Icons with a check on it; click that.
4. To return the appearance of your desktop items, repeat steps one through three.
Its a pain
but if you do image copy of the drive for production then its worth it