Impossible to answer. Don't have just one....but have got hundreds on hundreds of dvd's. All comes down to mood. So rattling some off the top of my head now I'd have to say:
Devil's Backbone; by Guillermo Del Toro ( he of hellboy fame etc) This film has the lot.
Adventure, Raiders of the lot Ark, Harry Potter films. Sherlock Holmes (Old Basil Rathbone versions)
Scifi: I love most scifi and collect all I can find...faves is tough. Them!, Fiend whithout a face, Bladerunner, Day the earth stood still, The Abyss.
I also like Leon, Jaws, Pulp fiction, Angel A: Tim glad you enjoyed it...great B/W
Western: Tombstone, Once upon a time in the west.
War: Anything with John Miles in. Also Saving Private Ryan, Zulu.
Animation: The Incredibles.
Horror: Hellraiser.
Bond: You only live twice.
Comedy: Tough one...they fit more into guilty pleasures...Overboard, How to murder your wife.
If I had to cut it down I'd go with 'Devils Backbone' and 'leon' at the moment.

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