Evangelicals frequently tangle over the literal nature of Genesis 1-2. A recent dust up once again exemplifies some of the whos, whats, and whys of this long-standing debate. The first article below is by Justin Taylor of Crossway Publishers and The Gospel Coalition, stating why he does not believe in literal 24-hour days of creation. Below that are an assortment of responses from the literal crowd (in which I find myself). Some of these are direct responses to Taylor, and some are older articles that simply help explain why we ought to hold to a literal creation week of six 24-hour days.
Regardless of where you stand on the issue, I hope the following articles will be helpful to your thinking on this very important theological point.
Older Article by Al Mohler on why this topic is so crucial
Kevin Bauder article against theistic evolution