We use Xubuntu (Ubuntu with XFCE). It’s stable and safe to update for non-geeks. The XFCE desktop mostly just gets out of your way and lets you work, while giving some handy features like snap-to-edges and such.
There are some minor annoyances with XFCE though, notably
- The default file manager Thunar has some crashes, e.g. on copy-paste. The XFCE people are aware, but it’s certainly taking some time to fix
- No built-in support for colourd; you’ll have to do some extra work for calibrating
- The HiDPI theme is not very nice (but then HiDPI in general tends to be badly supported)
- No touch screen support for window move/scale (the way Unity lets you move/scale windows with touch screens is actually very handy)
But all in all, XFCE has the fewest annoyances for me, and also is both easy to use for non-geeks and scriptable enough for geeks (so I can dogfood what my gf uses).
I’ve used Arch Linux before; it was fun, but on every upgrade you have to read the fine print, and although pacman is great and AUR has lots of nice packages, recompiling them whenever a dependency updates is a real drag. With Xubuntu that worry is gone, and because Ubuntu is the most used distro, there are PPA’s (and soon snaps?) for most stuff that’s not in the official repos.