We saw this earlier this year on Channel 4, and it kept my documentary-loving , but bouncing off the walls ten year old son, enrapt for the next 2 hours.
At the end he CRIED because dragons didn't exist.
It's presented as a documentary, lacking only David Attenbrough creeping through the Jungle, sitting next to the Koh-lung while it eats a tiger.
It is well-written and coherent, with a considered version of dragon history, using every version of the dragon that has existed in global myth and art for the last 5000 years. It's hard to believe that it's not real.
The making of doc is interesting as these things go, but is really only the sideshow to the main feature. My only gripe is that the CGI, whilst brilliant, isn't as good as Framestore (the BBC Walking with Dinosaurs series, Dinotopia) but hey, when every thing else is this good, that's minor.
Anything else? Yeah, one on unicorns, please!?
You will come away from this feeling that dragons don't exist, but they should. I recommend you get this DVD. My son recommends you get tissues.