I want to start my post with truth: "And you shall know the truth, and the truth shall make you free". You have come to the right place to know that "The Truth" is but a big lie, and not only that, but the source of terrible misery for many. In my humble opinion, you have to tell your children the truth. It will shine on its own, and will prevent them from wasting their lives, and, just as a witness is impossible to convince when on "defense mode", your children won't be converted no matter how hard anyone tries.
I am an unbeliever, worldly, whatever. So I am on your side of the fence.
I think you should try to send messages to Gary Neal, Greenie and Confuzzled. They are all "worldlies" like me. Gary Neal is married and has a daughter, and therefore he may have one thing or two to share with you, and you with him. Gary has a channel on You Tube, too.
You need to be careful because your wife, your children's mother, is a good woman with good morals. She is doing what her conscience tells her she should do. She is not taking the children to the Kingdom Hall because she believes they will be damaged. Try to tell the truth about her, too. She's a great woman, only a mistaken one.
I suggest that you read a lot, in this forum, and in Free Minds and JWFacts. You can find those with Google (I don't remember the web links). Depending on how you think your wife would take it, you could get "Crisis of Conscience" and "In Search of Christian Freedom", by Ray Franz, and "Combatting Cult Mind Control" and "Releasing the Bonds" by Steven Hassan. Read them, and you will have some more ideas about how to fight this. Also, your wife might be tempted to read them, and might just be helped to leave The Lie.
Be patient, and read, read, and read. Be very careful what you do.
I am of the opinion that, if the general public knew how witnesses look down on "worldlies", many people would never join the society. I guess your children wouldn't, either.
Make sure you help your children see the truth and stay free.