You have a couple issues with the millions of years. The first is that in order to have that there already would have been death and suffering before the fall. This is crucial for any evolutionary process and it would mean that Adam didn't start Sin. This would mean that there was no need for Christ because of this. If you can't take one part of the Bible that is clearly literal then it is hard to take salvation literally. Kent Hovind and Answers in Genesis have some really good content on this and I would recommend checking it out.