get that for the mouse its a gel pad not to hard or not to soft. It's a Fellows pad. Then I have the microsoft intellipoint 5.0 with tilt wheel (side scroll). I like it because it fits the shape of my hand.

For the keyboard, get a pad also or a keyboard with the extra piece of plastic at the bottom for the wrist. I'm on pretty much all day when I can and I have no problems so it should be easier for your dad

yeah I know it's dirty, its like 6years old