Hi Purplily, I think your father would be good with a Chromebook. Everything I hear and read suggests they're a great machine for people to start out with, (as well as being fine for experienced users.)
I am a volunteer teacher for hundreds of seniors computers and software at large senior centers here in Colorado. I would love to show them this laptop. Their hands are at times weak, and have problems holding a mouse. Will the mouse pad help them?
One of the problems is that the mouse goes too fast. Can you control the mouse speed?
My father in law is 89, and also has great difficulty with the keyboard and mouse, and even some difficulty with knowing that he needs to go to a browser to do things on the web. This would seem to solve the conceptual problem, as the browser becomes the web. But I'm not sure how to get the kb and mouse issue solved. When he sees a click here type message, his first instinct is to put finger to screen, so maybe a touch-screen would be best for him. Or a tablet.