Why aren't the books of the Bible in chronological order? Don't we have a good idea of when each was written? Wouldn't it make more sense?
Chronology is certainly one really good way to organize the books of the Bible, and some people may prefer this.  There certainly are editions of the Bible in chronological order that are available.  It should be noted that the order of the books of the Bible is not inspired, so you are really free to organize them however you want.

One of the problems with chronology, though, is the overlapping of some accounts. The book of Acts covers quite a bit of history, so the epistles occur throughout it.  Furthermore, there are some books that are not historical in nature, like the Psalms, Proverbs and Ecclesiastes.  Sure, they were written mostly by David and Solomon, but there really isn't a lot of reason to place them in between chapters of 1 and 2 Kings.

That being said, there is a common order that does have a purpose.  This historical narratives in the Old Testament are pretty much in chronological order.  The prophets span several kings and are not written historical narrative but has prophetic utterances in history.

One of my favorite representations is found in the Periodic Table of the Bible



The divisions highlighted here are as follows:


Pentateuch (Moses)
History Narrative (chronological, for the most part, with some overlapping)
Wisdom Literature
Major Prophets
Minor Prophets
Gospels (generally chronological, but each overlaps the others)
History (Acts) - chronological
Letters to Churches, named for cities
Letters to Individuals, named for recipient
Letters by People, named for authors
Prophecy


So, again, order them however you want for your personal reading.  If you don't like the common order, that's totally fine.  I remember an old mentor of mine reading through the Psalms backwards, which was an interesting idea.