Question: "Can / Should we interpret the Bible as literal?"
Answer: Not only CAN we take the Bible literally, but we MUST take the Bible literally. This is the only way to determine what God really is trying to communicate to us. When we read any piece of literature, but especially the Bible, we must determine what the author intended to communicate. Many today will read a verse or passage of Scripture, and then will give their own definitions to the words, phrases, or paragraphs. But, this is not what God intended. This is why God tells us to correctly handle the Word of truth (2 Timothy 2:15). In order to understand the Bible, we must realize that it was written over a period of 1,500 years, and was finished over 1,900 years ago. We need to understand the culture in which it was written; we must also consider the context of words, phrases, and chapters. At the end, I will recommend a couple of books that will help in understanding Scripture.
Though books have been written on this subject, I will write briefly on this subject and give you one or two examples of why we should take the Bible literally. We should take the Bible literally because the Lord Jesus Christ also took the Bible literally. Anytime the Lord Jesus quoted from the Old Testament, it was always clear that He was taking it literally. As an example, when Jesus was tempted by Satan in Luke 4, Jesus answered and quoted the Old Testament. It is clear from the context that He took the Bible literally.
Also, the disciples took the commands of Christ (which are part of the Bible) literally. Jesus commanded the disciples to go and make more disciples in Matthew 28:19-20. In Acts 2 and following, we find that the disciples took Jesus' command literally and went throughout the known world of that time preaching the Gospel of Christ and telling them to "believe on the Lord Jesus Christ, and you will be saved (Acts 16:31)."
As I stated earlier, books and books have been written on this subject. Just because you take the Bible literally does not mean that there are not figures of speech. An example of a figure of speech would be that if someone said "it is raining cats and dogs outside," you would know that they did not really mean that cats and dogs were falling from the sky. They would mean it is raining really hard. There are figures of speech in the Bible.