Welcome Lisa. keep up the reading and the experiments, you will learn so much as you go.
Don't worry about feeding your children, I'm sure you and they are both doing fine so far. Meat, fruit, veges and dairy are all primal.
You can begin to unobtrusively reduce the wheat by for example serving rice and potatoes more often than pasta, they may not even notice for a while.
Make the good food so tasty and delicious that they will not even miss the junk.
Rice bubbles and yoghurt go down well with kids instead of toast.
Primal pancakes can be made from bananas and eggs.
The children are young enough to learn good habits from you at home, I know it is disheartening how often other people will ply them with total garbage but there is not much can be done about that.
Oh, just noticed about your vegetarian husband - well maybe when he sees how delicious your food is he will come around. Bacon is almost irresistable IMO.