My first pick will be the movie I have watched more times than any other.
It is eminently among the most quotable movies of all time - with a line for nearly every situation. It's characters, from major to minor, are iconic. Featuring a fantastic soundtrack, a collection of the some of the greatest (and often most underappreciated) actors of its time, this movie is a cultural bedrock for my generation.
It represents a balance between nothing and everything; it draws a line in the sand that spares us from the threat of emptiness in life while reminding us to stay cool on over-zeal.
For its ups and downs, its strikes and gutters, my #1 pick is proudly:
It ticks off only 2 boxes, #'s 3 & 10, but sometimes you eat the bar...