The Thin Blue Line by Errol Morris - got a man released from Death Row. Doesn't get better than that.
Pumping Iron. Gov. Arnold v Lou Ferrigno and a look at the bodybuilding world circa 1976.
Hoop Dreams. Probably the best documentary of the 1990s. It is an unbelievably good film.
http://rogerebert.suntimes.com/apps/...IEWS/410210301