I have toyed with getting one of the package deals from
www.computergeeks.com .... for my own amusement.. and partly to see how well it would work. Their offerings seem to change... before they were offering a pretty complete system (minus monitor and OS) for $270... right now their only thing showing is a system minus HD, RAM, CD/DVD, monitor and OS for $99. JDR also offers some bare-bones packages of parts.
But, I'd never give it to my parents. I encouraged them to buy an HP Pavilion--not necessarily my first choice, but they weren't comfy with mail order so they wanted something they could buy at Circuit City--and like Wolf says, there'll be somebody besides you they can ask for help. (But they'll come back to you anyway.)