I am in a somewhat similar situation, although I have no children. As has been suggested, acquire and read "Combatting Cult Mind Control" -- that book helped me in so many ways. The natural, instinctual reaction to come at things directly can actually be the exact WRONG thing to do with a believing JW. All you accomplish there is bringing out the cult personality more and more, keeping the person on the defensive; it can really backfire very badly (voice of experience here LOL). Since reading that book and others (and doing a ton of research over a period of years), my situation has improved greatly from where it was, but there's still a long way to go.
If you learn the subtler and more effective ways of getting your wife to think, you have a much better chance of getting her to wake up, especially since she's not particularly diehard and rabid right now. The diehard rabidness comes out when you confront directly. Logic doesn't work with JWs, at least not while their minds are still firmly entrenched.
The fact that you have a child makes things more delicate for you. In your shoes, I would do everything I could to ensure safety for the child above all else -- the last thing you want is to end up with your wife estranging your daughter from you and raising her in the WTS.
I hope things work out for you and your family. The best advice I can give is to research thoroughly, understand the mindset and how to best approach (and not approach) it, and then act carefully and slowly, as opposed to rashly and quickly. Best wishes to you.
