BTW, it helps to set up their machines with their accounts as having standard user (limited user) rights with a strong password for your administrative account.
This means that you need to logon whenever they want to install something.
http://www.dummies.com/WileyCDA/DummiesArticle/id-350.html
http://www.informit.com/articles/article.aspx?p=478948
To enable Remote Desktop on Windows XP Home:
http://www.mydigitallife.info/2008/06/14/install-and-enable-remote-desktop-in-wind...
Remote Assistance or VNC might be better options.
