Link to Catholic Answers Radio Show on the Inquisition
As for the BBC video, I believe it is only available for purchase to Colleges and Universities. Someone needs to push to make the video more widely available.
Henry Kamen wrote a book on the subject. His sources and conclusions are much the same. The Inquisition had only one real bad patch, while Torquemada was Grand Inquisitor. That was when Ferdinand and Isabella were unifying the country.