The one I linked might be a good one, I think I've used it but I'm on holidays so I can't check.

The real wisdom here is, where possible, implement a basic configuration class and serialise it out to a file using a library, then only tweak it.

In your class you can have everything strongly typed and assigned and so forth and all the joy of a good IDE helping you along, then you can use the tiniest console app to just serialise it to a file for you and the syntax is guaranteed to be perfect because it's a tested library.

You don't even really have to learn yaml and it'll be perfect. If you need to tweak it it'll still be pretty easy because all the values and structure will make it clear what's happening.

Obviously less useful for people who aren't devs, but we are so we might as well play on easy.