Ok so the kids are not citizens, and she will need to apply for an immigrant visa for each of you, by filing an i130 petition for each of you. See the guides at the top of the page. It will probably take at least a year at this stage.
If the children are still under age 18 at entry on their immigrant visas they will automatically become US citizens at that point (assuming you will live in the US with their citizen mom as part of the household). You will be able to apply to naturalize after 3 years if you remain married to your wife for that length of time.
