I concur with this experience. A few years before my grandmother died, I installed Ubuntu on a new laptop for her. All she wanted to do was check her email, view her bank account and play solitaire. It was easy to set up shortcuts to any of this, and she never had any problems.

Every time I came to visit, I would make sure to check the status of the packages, and run the software updater if any updates were available.

The only 'problem' I experienced was confusion from my uncles, when they tried to use her laptop, when they came to visit. But I wouldn't really rate that a problem, since they just gave up and didn't ruin anything.