I think it is the best deal to create a user account that belongs to the 'users' group and restrict everything the dude does not need.
Including things like regedit, control panel, run box, cmd prompt etc.
Make a box with one entry in the start menu: programs and have the programs he needs preinstalled.
Also remove all icons from the desktop. I believe this can be done by using gpedit.msc otherwise find some registry tutorial.
Like this one:
http://www.easydesksoftware.com/regtrick.htm

Cheers
noODle