There was a rumour at one point that the original 20 minute pilot episode of Buffy was going to be on the DVD. Was that ever the case?

No, that was never seriously considered for the season one DVD.

Sometimes the discs have the original network trailers, sometimes not. Why is that?

That would just be a space thing. So for example on season one in the US we did put some trailers on, but we might not put all of them on because we may have twenty minutes space left that we have to fill up. If we put on ten trailers then we�re suddenly down to twelve minutes video space and it�s difficult to add something of any value in that twelve minutes space.

It�s always a question of balancing what material is available and what space is available. We could literally fill up all the spare space on the disk after TV episodes with trailers, from all around the world. It�s quite interesting to see how Buffy is translated into as many languages as it is. It gives some idea of the popularity of the show.