koreanjourney

Yes, I'd probably send in the I-130 just to make sure that doesn't have any issues now because once approved you don't have to schedule your interview until you want to. I'd call them after a month if you haven't heard back from USCIS by then. Then I'd make sure to gather all documents for the "packet 3" (they send you a checklist) and schedule the interview for 4-5 months before you want to leave. Schedule your wife's health check at one of the approved hospitals around 2 weeks before the interview (results take a week to come back) and then remember to electronically submit your "packet 4" before going to the interview. The info. is all at http://www.ustraveldocs.com/kr/kr-iv-documentpreparation.aspunder the headline "Cases not processed through NVC"
We have our interview next week so that's our next step, so I don't know any more from this point as of now.
My husband and I haven't have any children yet, but when immigrating I'm quite sure you'd put him on the forms as a dependent. There are spots you fill in for people you're planning on immigrating with.
My husband and I found that the Seoul office has a very specific way of doing things, which is why it can be much quicker to do it in person through them. So we relied on calling them directly and using the Seoul Embassy website since a lot of the info. given online had been too general (like suggesting we use the Chicago Lockbox, 1+ years of waiting, etc) which is all true if you file from the U.S or don't go directly through the Seoul U.S Embassy.

Just a note specific to Korea. Don't send your I-130 petition to the Chicago lock-box if you're going to do the VISA in Korea. This takes a lot longer to process than directly submitting your documents at the Seoul embassy IN PERSON (which you can do if you're in Korea on a VISA yourself).
We submitted my husbands I-130 peition in October of 2014 and received approval after just 7 days, however there was an issue where my e-mail wasn't accepting the US embassys e-mail and so I didn't know I'd been approved until I called the embassy myself in December. So if you don't receive an email within a few weeks I'd call them).
The embassy then sends you a list of documents you need for your "packet 3" which you bring to the interview (you can usually set up the interview date for a month after approval) and they'll review the documents right there. If you send it to the Chicago lock-box you'll have to send your documents along first and have them approved (I've heard this could take months) and THEN the embassy will give you an interview date for a few months after they review your documents. Which means another step.
My husband and I could have set up our interview back in the fall had we gotten the embassy e-mail, but we didn't want to be in the U.S until this coming summer anyway so we couldn't have set up our interview that early. (You must leave Korea within 6 months of your medical checkup which is required before the interview).