To be honest, the interview may not do much for non-Moore fans. In fact, I think Moore comes off a little bit . . . silly, and forcuses more on the image of Alan Moore than the talent. Despite a few (literally, two) talking heads, the interview doesn't do a great job in explaining why Alan Moore is considered, without hyperbole, to be one of the greatest comic writers ever, But if the movie has you interested in the comic, then this isn't too terrible a primer about Alan Moore. At the very least, it fully warns you what you'd be getting yourself into. :)
NOTE: As of 3/19/06, the video I link to above does not seem to work any more. If you're interested in seeing the BBC interview, try a youtube search for "Alan Moore", or perhaps another video sharing site might have it.
I am having difficulties watching the movie. I press the play button but it just sits there and doesn't respond. I then tried "sharing" it with myself [emailed it to myself] and then opened it from my email account. When I tried that, it said that the user has deleted the video clip. Is there any way you could put it back up?