I read both Greek and Hebrew. In Hebrew last year, we did word for word translations, then compared them to various versions. ESV came up as the best option every time. KJV is nice for fancy language, but I really found it impossible to read all that early modern English, and it doesn't hold up against the original languages. I have a United Bible Societies Greek Bible which has ALL the variations on the early manuscripts. Sadly, KJV used mostly later manuscripts which had been corrupted by Greek scribes. They loved to "embellish" the text. So Textus Receptus is really not the best use of the earliest manuscripts. As far as a version for a young boy, I like the suggestion to use Biblegateway.com. You can compare 5 versions at once, and change them at your leisure. They also have Greek versions there. If he is looking for word to word literalism, he is best to stick to ESV. If he is looking for a more dynamic translation, I would suggest looking at very modern versions like The Message. Of course, you do need to compare, as sometimes Eugene Peterson does tend to stretch things. I am in a Bible study with over 100 pastors, missionaries and Seminary profs, (mostly Baptist) and the Message is the choice by far. Of course, these people all know the Bible like the back of their hands, including the original languages, so when they find something interesting, they like to share.
In the end, reading the Bible means praying and being led by the Holy Spirit each day. As for NIV, never found a version I disliked more!