As someone who works in a comic book store, I can tell you that these movies don't affect the price of comics at all. There'll be a very brief spike when the movie comes out, but dealers aren't interested in buying stuff at that time, only selling. The only Batman stuff done in like the last 20-25 years that's really worth anything, I'm pretty sure, are the 4 parts of the Dark Knight Returns, and the first printing of The Killing Joke (which has like 11 printings). Even if this is the sort of stuff you're talking about, it will probably be hard to sell them now as most of the buying takes place by speculators before the movie comes out who think these will skyrocket in price, and are invariably wrong.

Spider-man 3 created a larger boost because the first 2 spidey movies had done exceptionally well for comic book movies, and because Venom was in it. Demand for Secret War #8 (first Spider-man in black suit) and and Spider-man #300 (first full Venom issue) increased, but it died down very quickly.