Of course you will be the one giving support! Your selection seems sound, balanced and not too high strung. You mentioned they would be on a wireless network yet you have an ethernet card and a modem. I presume you mean a wireless network card through which they would somehow connect to the internet. So, why the modem? Fax? My only thought is to not put in any hardware that will have no regular use and be a potential liability. When I look up the MB you intend to use it already has on board LAN and sound. Are the SB Live and and additional ethernet card necessary (unless you meant wireless card)?
I'm salvaging our old Dell and am building my parents a new computer, so basically they will be able to run XP, and a wireless network. This is what I've decided to go with, the + indicates that I already have this piece of equipment...Pro/Cons?
+Case
Power Supply = Ultra 400Watt ATX Power Supply with 120mm LED Cooling Fan - Black (50)
+Fan
+Floppy
Motherboard+Processor+Heatsink = AMD Athlon

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