I've read the book by Neil Gaiman and Terry Pratchett years ago and absolutely loved it. If you haven't read it: Do it!
The TV-Miniseries is, well, difficult to say. I guess it's more fun if you haven't read the book. It kind of covers most of the book story, but somehow (understandably) a lot of the irony (especially the thoughts of the characters) are missing. Still, watch it if you are into weird stuff.