Chapters in a book traditionally start on a new page, usually a recto page. Sections instead do not start on a new page.
I can think of some situations, though, where starting each new section on a new page would not be a terrible idea. For instance scientific books or manuals, where it may be useful to quickly locate and emphasize the bundles of information that are organized into a section. Such an idea might also be useful in a book draft, where changing a section may have disruptive pagination effects (e.g. with floats) on subsequent sections.
Do you know of any examples of books that adopt such a practice? Or do you have any insights to share on such an idea?
Personally I wouldn't start with The Colour of Magic, as it's not the best. He was very much trying to find his style with that one, and while it is a decent book, most would say to start with either Equal Rites or Mort.
The great thing about the Discworld books is that you don't really need to read them in order and can jump around the series without spoiling anything. Check out this image, it shows the series within the whole. I'm very fond of The Watch series, as well as The Witches, and Death series.