On-screen Keyboard

I hope this is the right place to put thisquestion. I love to use the windows XP on-screen keyboard when I fly. However it only works in window mood and not it full screen mood. Can this on-screen keyboard be made into an add-on gauge? My main goal is to be able to fly full time in full screen mood and use the on-screen keyboard to communicate with ATC.(1,2,3,4,5,6,7,8,9) The main idea is to not have to look down at my key board while I fly. Can this been done?
If you're going to grab the mouse and click on something anyway, why not just click directly on the ATC window's menu item you want to select?