I remember watching a lot of documentaries on NF back in Canada - they had plenty of stuff related to WW2, Hiroshima, the Vietnam War, and a couple of interesting ones about Russia.
That and old Godzilla movies.
I usually don't care much for blockbusters either, though I'm a sucker for silly comedies - all those Will Ferrell movies, the SNL and Judd Apatow stuff which always feature the same bunch of fellows, like Seth Rogen and the rest of those guys. They often have the older ones on NF.