The bottom line:
I can keep my son from installing programs on my computer.
No program, virus, email attachment, etc... will run unless I approve it and enter my password. Seems to work so far.
There is a free trial period, but I would recommend checking this out BBoy since you seem interested in protecting your computers...
Reply if you download this software or know of something like it thats free. hehe
The link is http://www.seventhknight.com