[DanielleMolloy]

I had a set up of my old computer with xubuntu for my mum for 1.5 years and had to learn that Linux is just not stable enough in the long run if installed for a novice user or as a "parent PC". Don't be naive here; even automatic updates will too often either break something or confuse users unfamiliar with computers. And you will need to be around to fix it or they won't be able to use that computer anymore.

I ended up buying her a second-hand MacMini for 110€ more than 2 years ago. Old enough that it still was a PowerPC version. It still works very well, never needed to fix something, it is fast enough for her use cases (e-mail, digital camera, some internet surfing), and she loves it. If things get messed up on OS X they do that in a "user friendly" way, and she (before being mostly annoyed by computers) has started to become quite proud if she can fix such minor issues by herself, or with only little guidance. I'd say she acquired some general computer literacy through using OS X, but not through using either Linux or Windows. She now likes Steve Jobs.