You could also try "Tweak Manager" - a program that lets you apply all sorts of restrcitions, which include preventing access to Control Panel, or just some of the items within Control Panel.
( There are over 1000 different "tweaks" that can be applied via a simple windows type user interface ).
The restrictions can be applied to individual users, so you can remove the Control Panel access for one user, and leave it available to others.
You can download the program for evaluation for 30 days for free here : Tweak Manager 2.1
If you are as impressed as I was with the program you can then pay the licence fee ( US $39.95 ) for the full product, or if not just uninstall it.