This minimalist DVD consists of footage shot by people with cameras on the day, all put together in chronological order, to create a sort of montage of what happened. There is no commentary, the sequences speak for themselves. I think it is probably essential that you also watch the bonus section which features the people behind the cameras talking about their own experiences of that day, and why they filmed it; I think the bonus feature is actually better than the main feature! A dramatic shot of the second plane hitting the tower, filmed from below, is featured in the bonus section but not in the main one, for some reason.
The DVD as a whole conveys quite well the different emotions and reactions of people on the day, and also the scale of the devastation after the towers collapsed. I thought at times, though, that it got a bit repetitive; how many different angles do you need to see the burning towers from? And one more thing; there was a shot of one of the towers going down that I haven't seen before. The way you can see it starting to collapse near the top where it is burning, shows quite clearly that it was NOT the result of a 'controlled demolition' as the conspiracy theorists claim.