i think only masashi kishimoto knows but its something about how to get girls based on the information jiraya uses as writing material. also the first one make-out Paradise is probably a story on how someone got a girl but the sequel "make-out tactics" pretty much gives away what its about.
yes in book 27 it tells the story of how he got it
His face
Grey or White.
kakashi chronicles
No, she is dead.
Yes she is dead, but noone knows how.
september 15
No. It is not shown in the movie
Kakashi's full name is : Hetake, Kakashi
She's unkown, but it's stated in the manga that she died very young.
Sakumo Hatake (or Hatake Sakumo) is Kakashi's father.
She is dead, but noone knows how she died.