RE: keyboard issues. Chromebook has some oddities like a search button instead of caps lock and a combination of ctrl or alt & arrow keys for page up/page down and home/end. Function keys replaced by browser control keys. It's actually very straightforward and probably better for a technophobe than F1, F2, F3, etc. As long as she won't miss that caps lock key
Ordinarily I don't like to recommend OS X but if you're looking to spend Pixel money on a computer, a Macbook might be worth considering. It is relatively straightforward to use and support is readily available online. And it's strongest selling point (for me at least): IT ISN"T WINDOWS!
I will say that unlike a lot of low end computers the two cheap Chromebooks are actually pretty decent machines. The C7 is upgradeable (RAM and HD) and while the battery isn't so good, it can be made into a pretty speedy machine for a fraction of the cost of the Pixel. The Samsung 3 is a complete package with a lot going for it (no heat, no noise, fast, long battery life) but of course they are both low-end computers so they have some build quality issues and the screens aren't very good. Still, if you're talking buying a $1300 web browser (nothing wrong with that, the Pixel is awesome), then maybe $200/$250 isn't such a high price to pay to give the OS a go for awhile and see if it is something that will work for you.
You mentioned your wife is older, does she have special needs like a larger screen or better image quality that would necessitate spending more on a laptop to ensure you have a good screen? One last thing I would recommend
Laptop Reviews - Notebook Reviews and Computer News
Notebook Review is an excellent website that covers laptops of all sorts. It has a fairly decent forum community, including an entire forum dedicated to giving and receiving advice on what kind of laptop to buy. If you are still totally on the fence you might get some better advice there.