I've just taken the afternoon off with my wife to see The King's Speech. It's a movie that I highly recommend. As a stammerer myself, I found that I very much lived the film.
Be warned, spoilers follow!
The film opens with Prince Albert (Colin Firth), second in line to the throne, preparing to give a speech to close the 1924 Empire Exhibition. He must speak in front of the large crowd at Wembley, and his address is transmitted live around the world on the new wireless radio. He struggles to start the speech, and continues to stammer (with a lot of long and silent "blocks"). Colin Firth conveys this upsetting, traumatic and frustrating experience well, so that I think many in the cinema audience would have shared the discomfort of the crowds watching in the film.