So... with moving my house and the office (where most my old computers live), there were plenty of extra parts to build him a pretty nice computer.
We brought it over last night and I got my first experience introducing them to a mouse. It was a crazy experience watching them learn it. I had to bust out a lot of analogies about the mouse and the Internet. I opened up the computer and showed them all the (few) parts and what they do, so it wasn't so mystic.
The setup is Linux, GNOME, and GDM logging them right in without a username/password.
Yesterday they learned to turn it on, play Blackjack, and shut it down. Also minimize and maximize, so they can switch between games while she cooks.
Saturday we show them the Internet and how not to fall for Nigerian scammers.