As for reading what Christians call The Old Testament, I think I'm probably one of, like, 3, who's actually read it. The book of Ecclesiastes is the one that seems to speak the most directly to the Human heart. That and - perhaps - The Book of Psalms. As to which version of the bible is more accurate, regarding these two, I'm not sure. In the rest of The Old Testament, it's very hard to find God's word, as it might apply to someone's actual life. Mostly what he seems concerned with is that the Jews stop making him jealous with false gods, or with the precise measurements of specific religious objects, like the Ark of the Covenant, or to do with deciding which King(s) will rule Israel. Without a Rabbi, or a priest to guide you, it's an extremely challenging read.

In the New Testament, with Jesus Christ, there are certain books that are strongly suspected, or outright known to be authored by, say, Peter, or Paul, or whomever and scholars are pretty sure about those. Several books, however, are suspected to be written in Paul's name, like some in the Acts of the Apostles, for example, which are believed to have been Luke's handiwork. It is not universally accepted as a given, but there's a strong belief that the book of Mark was the first Gospel written. Also that it was written by Peter's assistant, who happened to be named Mark and is therefore considered the most "accurate," having been dictated by Peter, himself. The Book of John, of course, signs off on it with the declaration that he, the author, is John the Apostle, Jesus' favorite. But even that seems to follow Mark's narrative, at least roughly. As to reading these in American English, or the King James Version, I'd argue that the American version is the more accurate. King James sounds very respectful and appropriately dignified, but nobody talks like that, not even politicians. Personally, I find KJV to be extremely distracting and sometimes confusing. And every Bible I've personally seen has specific notations where a word or phrase was replaced, with the original, or alternative meaning in the footnotes.