Immigration Law Questions? Ask an Immigration Lawyer.
You have a few options. The fastest would be for you to file an I-130 and I-485for the child. This will be an immediately available visa, and the child can get a social security number (good at tax time) right away if you do so. Her I-130 that she filed can remain until she becomes a US citizen (she can file in 3 years as a greencard holder/spouse of a US citizen). The I-485 could then be filed for the child based upon that I-130, but this will clearly take longer.
As for citizenship for your wife, it sounds as though she was a greencard holder prior to her marriage to you. Is that correct? Assuming she meets the good moral character requirements and the physical presence requirements, she can file after 4 years and 9 months of being a greencard holder, without regard to her marriage to you, or, if filing based upon her marriage to you, after 2 years and nine months of being a greencard holder and the spouse of a US citizen.