I knew the correct answers for #25, 19 and 23 before I read the commentary in late posts. #36 is just a guess based on the fact that you already said it's Woody.
8. "It's a hell of a thing killing a man. You take away all he is and all he's ever going to be." - Clint Eastwood in Unforgiven
10. “Did you know the human head weighs 8 pounds?" - Jonathan Lipickny (sp?) in Jerry Maguire
11. “You’re not gonna say that now! You’re not gonna say *that* NOW!” - Jack Nicholson in One Flew Over the Cuckoo's Nest
14. “It wasn't a miscarriage. It was an abortion.” - Diane Keaton in Godfather II
18. "Everyone wants to be us." - La Streep in The Devil Wears Prada
19. “Leave the gun. Take the cannoli." - the guy who played Clemenza in The Godfather
20. "What do you want me to do? Dress in drag and do the hula?!" - Timon (Nathan Lane) in Lion King
23. “In short, to recap it slightly in a clearer version, uh, the words of David Cassidy in fact, uh, while he was still with the Partridge Family, uh, ‘I think I love you’” - Hugh Grant in 4 Weddings...
25. “There is no America. There is no democracy. There is only IBM and ITT and AT&T and Dupont, Dow, Union Carbide and Exxon. Those are the nations of the world today” - Ned Beatty in Network
28. “She needs me. It's not as if she were a maniac, a raving thing. She just goes a little mad sometimes. We all go a little mad sometimes. Haven't you?” - Tony Perkins in Psycho
31. “I was cured, alright.” - just a guess, Malcolm McDowell in Clockwork Orange
34. “Most people never have to face the fact that, at the right time and the right place, they're capable of... anything!” - John Huston in Chinatown
36. "The last time I was inside a woman I was in the Statue of Liberty" - Woody in Crimes & Misdemeanors
40. “Girlie, tough ain't enough.” - another from Clint, this time Million Dollar Baby