Linux Mint Debian Edition

Okay, you got me, this one isn't actually a server OS.

However, it can actually do just fine acting as a server.  It comes with a full desktop UI and graphical tools.  It resembles Windows.  It's generally the most user friendly and hand holding version of Linux under the Sun.  It also inherits the rock solid performance and stability of Debian.

The drawback, of course, will be a performance hit from the desktop and related apps.  I don't recommend it for a low cost SBC but it should still work on one.  Honestly, the performance hit shouldn't be super significant in most cases.

This is actually the OS I'm currently hosting most of my Docker containers on and it just works.  The setup has been super easy.  The only real issue I had was hardware related.  It has turned my little Intel NUC into my "do everything and a bag of chips" machine.

If I were determined enough, I could uninstall the desktop and the GUI apps and basically make it function similar to Ubuntu Server but I'd be better off installing Ubuntu Server, in that case.