Hi Pierced,
I enjoyed your comment about your kids and going to the park on Sunday. That is so much more productive for bonding with your kids than having to tell them to sit still every 10 minutes for 2 hours!!!
As to your question about my daughter, who is now 12 and at this point an athiest:
We went to fewer and fewer meetings from the time she was 2 until 4, when we quit going entirely. She was really too young to have the indoctrination take hold. On top of that, her Mom and I did not read Witness bible stories to her. We had 2 bible based storybooks: Jonah and the whale and the Noah's ark story, but they were generic, non-demoninational books. (I was already beginning to "stumble", er, see the light! )
We also never had prayers at meal or bedtime--in fact, rarely did we have prayers in my family at mealtime growing up on account of the fact my Dad was a non-witness.
In any case, I feel for your position with your son. I would encourage you, hard as it may be, to let him make his own decisions as he gets older. The grandparents will of course try to steer your kids to JW ways. I really don't know how best to deal with that because I imagine each family situation would have many variations. When I was first out I didn't have a clue what was "truth", but I knew (for my own heart and mind) what was not. I did not tell my Mom to not teach her JW things or take her to meetings. My Mom, I must say, is not the "model" witness and did not use the emotional blackmail of "your parents will die in Armageddon, etc."
I do know a lot of what you will be going through and I sincerely hope whatever happens, your son doesn't get blackmailed. If you think some of that may occur, talk to him about those scare tactics and how they made YOU feel, and why those things are not what Jesus would do.
Jon