That's when you wish you had spares, so everyone can work with Linux. I presented Dennis with Linux Lite its beginner friendly, if he doesn't like it I can send him a disk of Peppermint9 another easy to use OS. I went from 18.3Xfce to Cinnamon, I got my feet wet with the easy version.
On mine Windows7 resides on its own drive, Peppermint9 has one as does Linux Mint19.1. I can run from any of 3 OS's at restart.
I am now down to 3 laptops and I'll not be buying any more. I have a Dell disk for Windows 8.1. 7 rarely sees the internet and it runs the printer.
My sister already has the first Dell that I installed Mint 18.3 Cinnamon on about 2 years ago.
they use it as a backup/spare in their Motor Coach. Greg gets along with it just fine, all he does is click on Firefox and surf the fishing forums.
So, they already have one laptop with Linux.... it is stone cold reliable from what they say.
I chickened out with letting it update, as they will use it so seldom, and only with Firefox, that I felt it was not worth taking a chance that an update would crash it.
Since then, I have changed my opinion on that. This laptop that I am using as a Daily Driver, is using a CronTab job to install all updates everyday, as they come available. the job creates a log so I can review it to see what happened, if I so choose. but, it has been so long since I did that, I can't even remember when I last looked.
Mint 18.3 just keeps cranking on, everyday, doing what it should.
Timeshift creates a Daily OS backup, keeps 5 copies..
so IF, something went awry, I can just backup 1 day, and restore it like it was.
Only needed to do that once....... and it was my fault....
installed new software, and oops! it crashed.