Yes, you can read the Bible in a shorter time frame, but to keep the momentum going, it's better to pace yourself. Two hours a day (on average) works well. If you try to do too much every day, you run the risk of burning out and not making it to the end.

As for which version of the King James, that's your choice. You'd be reading it on your own. This isn't a public reading. We're just all reading the same part of the Bible at more or less the same time every day. You're welcome to join, even if you don't, as you say, believe in God.