Not sure how widely this will apply, as I have Vista 32 bit and an ATI card and most of the problems appear to be Win 7 and Nvidia related, but I got my game working. Ish. Anyways, had the same problem a lot of people had, the game would crash after when cut scenes were played (usually right at the end). Couldn't get to the main menu even when skipping the scenes via escape or pause.

Tried most of the solutions presented by others, none worked. Noticed a lot of the crashes I was getting a DEP pop up. So I decided to turn it off for Gorky 17. That didn't work. I had to set it to only work on essential Windows services. Now it more or less works. Cinemas still crash the game eventually, but I can ESC past them and play fine. Can even play in Hardware mode so don't need to deal with the annoying sounds of software mode.

TLDR: Set Data Execution Prevention to Windows essentials only. Setting Gorky 17 as an exception didn't work for me.