Are Set-Top Boxes A Solution For Novice Users?

OctaneZ asks: "While I know very few of us would consider a set top box as a good solution for a replacement of a home PC; there are individuals for whom these products would be perfect. I am looking for a solution for completely computer-illiterate relatives; and was wondering if a set top box might be a solution. I am not looking for sheer power, bragging rights, or gaming; just e-mail and Web access. Has anyone had luck with preconfigured set top boxes? and with those, how is the service? Also has anyone made a "roll-your-own" set-top box out of a MicroATX machine? Could a MicroATX implemetation be "deployable" to 3-4 users running LINUX or another OS, and not require regular maintenance or excessive amounts of teaching?"