I have a question directed for the comic book experts out there.?!

I have a question directed for the comic book experts out there.?

I'm assuming that the Batman movies are based off of the comic book, at least the first 2 and the last one anyways. Am I wrong? If they are based on the comic books, im curious as to how Batman's parents die, since the first movie has the Joker killing them, and the last one has somebody else? If none of this is accurate, what would be a summed up version of how it went down in the comic books?

"Based on" is not the same as "directly adapted from". The Batman films take many general ideas from the comics, but they are generally not based on specific storylines.

According to Wikipedia, Bruce Wayne's parents were murdered by a small-time thug named Joe Chill. The DC Universe has been through numerous complete continuity reboots, so the history of this pivotal figure has been muddied. In two previous versions, Batman confronts Chill, even going so far as to reveal his identity. In both cases, Chill is then killed by another criminal before he can reveal that Batman is Bruce Wayne. In the current continuity, Chill was apparently arrested shortly after killing the Waynes. What happened to Chill after his arrest has not yet been revealed. But the man who would become the Joker being the murderer of Bruce's parents was entirely an invention of the Tim Burton film. It has never appeared in any comic storyline.