As a newbie, I'd like to welcome you as well, as you've welcomed me in my thread.
The issue of religion and belief is a difficult one, but i think it's great that you're questioning and researching. Perhaps, after new years, we can exchange ideas about your doubts, it will help me reaffirm my thoughts as well (or question them perhaps, who knows?).
There always is the 'what if' when it comes to religion, isn't there? what IF islam really is the true religion, will I make a mistake if I renounce it, will I be doomed to hellfire?
For me, it went as far as to question my own humanitarian/liberal belief system. What IF mankind's 'fitrat' (thats how we say it in turkish-think it's 'fitra' or something like that in arabic?) really is as 'god' reveals in the quran? What if we really do need to chastise the non-believers, beat our wives? What if there really is a hierarchy among genders which we shouldn't question? What if god really does know best?
Tough, tough questions.. take your time, work in slow strides and go where your mind takes you. I for instance have renounced islam, but I still cannot buy into absolute materialism and positivism. That's my struggle, to make sense of the world and everything around me, to find a single formula that will help me decipher the codes of the universe. Religion makes it easy for you-it gives you the full package, just believe and everything makes sense

Being a rational human is hard I tell you.