I prefer using XML-based config files and using, say, XML::Simple to parse the file. It is just about as easy as parsing name=value files.
I sort-of second that, except that I'd use YAML. Even if one doesn't know it (I don't really), it should be easy enough to look at some samples and imitate them, or instruct one about how to do so in a few words. It's more human readable and writable IMHO.
They might. OTOH it might all be done by software. That wasn't specified.
Now, I agree that XML is not beautiful, but so many people who might edit config files probably are at least somwehat used to HTML, and even vim knows XML highlighting. I do not think it is a problem unless the config file designer goes wild...