If "just works" is the relevant metric, it's hard to beat Debian stable - or CentOS, or perhaps OpenSUSE Leap. Sure, the things you might be able to easily achieve with them are quite limited. But the flip side is that they will chug along nicely and reliably for years upon years, with nary a hiccup aside from the occasional security update. That's the sort of "just works" that we - and our non-technical acquaintances - are most in need of!