I had weirdly encyclopedic knowledge of old Finnish comedies because my late father was into that stuff.
Also: Not an obscure film, but to me, the definitive version of Terminator 2 was the one I recorded off TV. I have it on Blu-Ray, but it's just not the same.
Most times that I've watched Terminator 2 were when I happened to catch it playing on TV. It just doesn't feel right without breaks and tacky commercials.