Linux on the desktop can save you money if you know how to use it. You could setup a KDE system, that even a dumb dumb can use. In the end though. The user who has to use this PC will need to understand what they are doing in their alotted enviroment. Which for them won't be Linux, but the program they use to do their job. So really all you have to teach them is to use a program that does their job.