In The Irrational Atheist, Vox Day doesn't so much defend the Christian or Theist position. There is no need to. All he has to do is show that the Atheist position is so irrational that no rational person could be swayed by their arguments.
I would summarise Vox Day's position as "The atheists are liars, bad liars and can't even manipulate statistics properly."
One chapter covers the Inquisition, the Crusades and Human Sacrifice - all allegedly major problems that are laid at Religion's feet. I thought the best information was that children's bicycle accidents kill more people every year than the Inquisition ever did. 130 children's bicycle deaths per year verses 9 "victims" of the Inquisition per year. And as an aside, The Great Leap Forward by Mao Tse Tung killed 8,600,000 per year, but hey, that's not relevant.
The book is well written and very easy to read in small or large doses. Vox Day is so confident in what he has written that he has challenged any self avowed atheist to challenge any of the arguments he has made in his book. The response has been loud and blustery, but of no consequence. You can read it for yourself by downloading it for free in a variety of formats at his blog or buy it from Amazon or other booksellers.
Overall the book provides a great insight into the atheist position. The church's position has always been that as God made the world, it makes the most sense following God's laws for our actions within it. Any other position has varying shades of insanity - that is, a less than sane way of viewing the world.