I had heard about some movies that do not transfer all that well to Hi Def because of the limitations of the filmstock at the time.
But I will say this: One movie I am anxious to check out in Hi-Def is Star Trek The Motion Picture.
I remember sometime back gushing over how beautiful the film looked on my old 60hz HDTV, and that the film quality was such that it looked like it was shot within the last couple of years.
Now, with my 120Hz, I'm anxious to see how well it translates. I can only imagine it would be stunningly gorgeous, especially after having watched "Balance of Terror" in true Hi-Def.