Wow another hard one! (But now you can see why I took so long to post it LOL)
There are too many stories that I would love to make into a movie but my like I've said before, my favorite graphic novel is the Elseworlds title Superman & Batman: Generations and I think that would make a great live action film series.
Now, if I'm creating the plot myself...
The movie would be a trilogy at least, I don't think there's really a such thing as an effective standalone Batman movie.
Movie 1 would depict the death of Dick Grayson's parent and his introduction to vigilante life after Bruce has been Batman for a few years (3 or so years after The Dark Knight). It would a serious drama and Dick would be about 12 (I know in canon he's much younger but that's a lot of belief to suspend for film). Bruce would really see himself in Dick and would in his follow up after the parent's death would realize that the boy was claiming that his parent's death wasn't an accident and was being ignored by the police. Thus the villain of the movie would be Tony Zucco. It would probably center on how Dick makes Bruce confront some of his own issues and disturbs plateau that I think Batman tends to fall into (another case, another day: crime-fighting get's a little boring to me without some good ol' interpersonal conflict). Superman would be an established character and might also make a few appearances, expressing his concern for Dick and how he doesn't agree with Bruce taking a child out into the night. Obviously Dick would prove himself in the field, secretly following Batman as he executes justice and actually saving Batman in a crucial moment and also have that moment of truth where he has to choose between getting revenge and turning Zucco over to the police.
(At some point before Movie 2 I expect a Superman movie will have already come out and Clark and Lois's relationship will have been established.)
The next movie would reintroduce the Joker, Harley Quinn, and Catwoman as both criminal and love interest. Her neutral nature would be established in that she assists Batman in taking down the Joker and Harley Quinn and her support of women’s shelters from the proceeds of her... acquisitions. My Catwoman would be extremely intelligent middle class scholarship student who went to Excelsior but whose parents died when she was in high school and ended up getting into art thievery to pay for college and making a name for herself both as an jewelry thief and art/fashion historian. Dick would be 17 and still Robin, though this would be about the time that Bruce and Dick were having friction in their relationship, which will show in the film.
Wow this is getting long so I won't elaborate anymore :)