Linux

Nixos with whatever defaults you don’t want her touching, then she can use nix profiles to install extra software if she wants

Fedora Atomic desktops, specifically Kinoite with KDE6 works well for me, and is basically unbreakable due to the way it works.

Linux mint is a good, "click first" distro that won't break without root + will be easy for her to use. For something with a more modern desktop and more recent updates, Bazzite is really good at just working and (in my experience) has never broken

I've set up Linux mint for my sister in law and didn't hear from her the whole two years she was in college. But nowadays we have immutable distros. They're fantastic for a set it and forget it kinda thing. They're solid for those who don't want things to break.

Any of them. Just don't give the root password.

Aurora by Universal Blue. She will be unable to break it, and it's so freaking easy to use and install.

Use Bluefin or some other immutable/atomic distro.

The upside is that it's rock solid and will likely never fail in a way that cant be easily rolled back. The downside being that it's slightly more complex to administer than a traditional distro model (which probably isn't a big problem if you are going to be administering your SO's PC for the most part.)

Bluefin is basically a more general desktop, less gaming-focused version of Bazzite. Bluefin uses Gnome, but there's also a KDE Plasma version called Aurora.

An immutable distro would be a good choice. They are distros designed to be more resilient against failure. For a gamer, bazzite is a solid choice; otherwise, silverblue.

I guess it depends what she does on her pc.

But ignoring that, Mint without sudo. Throw in flatpaks and appimages.

Immutable distros are probably fine too but in my experience they tend to be a bit fussy if you need to change something in the system config.

Ubuntu, always a solid choice for beginners but Gnome shell is a bigger change from windows conpared to Cinamon.

P.S. I have Mint on our TV PC and my SO handdles it without issues.

Aurora or Bluefin would be great, general purpose distros. They're based on Fedora Kinoite and Silverblue, respectively, so you get that atomic unbreakability with the addition of some handy software and easy, optional scripts via ujust.

I have Bazzite on a laptop specifically for this reason, so if I ever kick the bucket early, they will have a reliable and portable computer.

Does she want this?

If so then just set her up exactly what you have so you can easily help when there’s a problem.

If not then get her the computer she actually wants.

I switched from ubuntu to debian when 12 was released and it's been fine. Only thing i was worried about was running WoW via lutris but had no issues.

So when my SO windows pc died we bought some newish parts and i installed debian on it as well. Also installed chrome since that's her browser of choice. She's still getting used to gnome, but all she needs is browser, WoW, and libreoffice, which is close enough that it hasnt been an issue. She doesn't even know how to update the system.

Debian is good at being basic, generic, stable AND has an automatic security-update-in-the-background feature

The whole amount of instruction to give to Dear SO is just to reboot the machine if it ever seems to misbehave

I thought this was a request for Stack Overflow proof.

Then figured that was 'proof from pasting random crap from SO".

Then figured it's the same thing.

Any distro will be suitable, create yourself as the first user when installing (which will probably be added to the wheel/sudoers group or whatever) then create a new 'standard' user.

Most distribution defaults should be adequate.

For added safety, choose one that is immutable like, for example, Fedora atomic.

Use btrfs snapshots. Bring the PC to a state that you like, make a snapshot. Then on shutdown set the profile to reload to the specific snapshot.

Any issues? Just restart. Might take a minute, but it ensures the exact same environment every time.