[jgoerzen]

The last version of Windows I used seriously was 3.1.

Last winter, I suddenly had to fix problems in Windows Server 2008. I may have been a bit slow, but yes, I can fix an OS I've never used.

If you have a good knowledge base, and the experience to provide a good intuition, you can figure them out.

I would, incidentally, consider Debian to be a modern OS, and a CLI to be a modern UI. If they can string together commands in bash, I'm sure they'll be just fine with Windows.