Blackcat, if you're at all inclined, this may be the perfect opportunity for you and your DS to be students together. Given the tenor of your religious upbringing and the lack of support you received as a child for testing and evaluating ideas in the faith, you might find it enlightening to dig into the meat of the faiths you're exploring to make up for post opportunities in childhood. I formed my religious views in grad school as a 20-something on a quest to prove atheism, after more than a decade of dissipated agnosticism. My family was loosey-goosey Christian with a weak religious education, so I mostly learned nothing about religion until I sought it out as an adult. It was so much fun to finally have some decent answers to old questions, or to have new questions arise!!
My favourite resources are Catholic because I'm Catholic. Posters from different backgrounds will, obviously, have other go-tos. I've listed a few below that I particularly relied on.
The single best resource in my journey was Aquinas' Summa Theologica (free full text linked below). I'd recommend tackling one or two ideas at a time in the Prima Pars. With any endeavour, the simplest step must be taken before more complex ones. Tackle the issue of the existence of God with your son first before getting into the idea of Jesus or any biblical events. The treatment of God will be the first step in evaluating any religion. Take it slowly, question everything, and keep digging for credible resources if your questions aren't answered adequately. There should be no contradictions between science and religion.
http://www.newadvent.org/summa/Enjoy! Whether you agree with him or not, Aquinas will keep your thought process on track!
If you want to hunt down other good resources, I found the Catechism was a good startin point. Everything is well cited, and the headings make for quick reference guides:
http://www.vatican.va/archive/ENG0015/_INDEX.HTM
