Choosing a Bible is an excellent little resource detailing the differences between the three major types of translations: essentially literal, dynamic equivalent and paraphrase. The literal translation, which was the goal of the translator until the middle of the twentieth century, attempted to translate the words of the original Hebrew and Greek texts as literally as possible. Today, the best known translations of this genre are the NASB, ESV, KJV, NKJV and RSV. The dynamic equivalent (or functional equivalent) translations are best represented by the NIV, TNIV and NLT. The goal of dynamic equivalency is not word-for-word, but the thought behind the words. Paraphrases such as the LB and The Message are not translations at all but running commentaries, i.e., opinions of the author.
Ryken demonstrates clearly the inferiority and danger of the latter two groups. What the dynamic translators give us, he writes, “is a translation plus a commentary” and, in the process, “diminish the glory of divine revelation by being more concerned with the human reader than the divine author” (p. 9). Additionally, “dynamic equivalent translations often make it impossible to know what the Bible means because they remove from sight what the Bible says” (p. 16).
Ryken does not interact with the manuscript issues behind the KJV-only debates so you will have to look elsewhere for those. But he has done a great job in showing the superiority of the literal translations. I agree with him completely.