We're big fans of this show in my household, even though my wife is not all that interested in scifi.
I hurt my back pretty severely and was flat on the floor for a couple of days. One of my sensei gave me a this to watch and it took my mind off my pain.
From what I've read, the original pilot was rejected by Fox and the second episode was shown as the pilot, instead. Shows you what TV execs know - NOTHING! They never, ever gave this show the shot that it deserved. And, unfortunately, it looks like it was Joss Whedon's shining moment, never to be repeated (sorry, all you Buffy and Dollhouse fans!).
There is a mini-series of comic books that span the time between the TV show and the movie. They can be a bit difficult to find, but are worth reading.
I also can't recommend highly enough the books that are published about the show. Especially "Finding Serenity" by Jane Espenson. Various authors analyze the show from every angle, proving that this was one of the best shows on TV ever, regardless of genre. Again, they are a bit tricky to find but are available and worth every penny.
One of my students has a daughter in her late 30s that runs a "Browncoat" fan club. That's how far-reaching this show was. It will forever be a cult classic.
Kelly Knight