Yeah the touch-screen has been a problem - especially when trying to give something out to the general unwashed public. No amount of protective cover would have helped us when some guy or gal decided to punch one of the screens in a few months back. Meh.
By 2" thick I was talking more about a box with the touch-screen in the front with a simple plastic protective layer and a hinge you can flip open to reveal the internals. That way replacing the screen is just a dispatch-call. Or something to that effect.
Basically something that can be mounted semi-permanently, the same way as a television screen, and with the most common parts (the screen) accessible by a technician so they can be replaced when broken.