One More Detour on the Writing Road

How do you turn off the commentary track on Buffy DVDs? When I watched them on the iBook, I used to have to stop the episode and remove the disc from the player, then reinsert it. Now with the TV hook-up, that doesn't work--when I remove the DVD and pop it back in, the play simply resumes at the place I left, still with the commentary. What's worse, there was commentary on the next episode, and that played as well.