newacct

3. no 4. yes No, it would not affect H4

Yes. Your Certificate of Naturalization plus her green card plus your marriage certificate showing custody of her. No. Unless you like to pay $1,170.

No. You petition each of your parents separately. Both of them are principal beneficiaries on their own petition, and neither of them are derivative beneficiaries (the Immediate Relative category cannot have derivative beneficiaries). You will file two I-864s, one for each petition. The I-864 for your mom will not list your dad as a "family member". The I-864 for your dad will not list your mom as a "family member".

You can stay in the US as long as your I-485 is pending but you cannot work unless you have an EAD.

no

You do not have waste your money to apply for green card renewal (which takes about a year anyway). If your card expires before you naturalize and you need proof of permanent residency for something (e.g. travel abroad), you can go to your local USCIS office to get an I-551 stamp, which they will give you since you have a pending N-400.

You can't petition parents to immigrate until you become a US citizen.

Update: USCIS has updated the AOS filing chart for July to indicate that F2A is current, meaning all F2A can file I-485 in July (either concurrently with I-130, or after I-130 is filed, regardless of priority date).

Update: USCIS has updated the AOS filing chart for July to indicate that F2A is current, meaning all F2A can file I-485 in July (either concurrently with I-130, or after I-130 is filed, regardless of priority date).

I think they have started denying applications that have missing initial evidence, and both photographs and I-864 are initial evidence for I-485, not follow-up evidence. I think you can file a Motion to Reopen with I-290B since you have new evidence that was not submitted before; you would need to file that within 30 days. Another option would be to file a new I-485, which you are still eligible for.

If she leaves the US while a timely-filed, non-frivolous Extension of Status is pending (i.e. before a decision is made), her visa is not voided. If she is still in the US when it is denied, her visa is voided, since she would have already stayed past the date of the denial by the time she learns about it.

Wait until you get the denial notice to see what reason they claim to deny you, and post it here so people can see whether the denial was right or wrong. The course of action depends on what the reason is.

It is possible to get a nonimmigant waiver. You would apply for your visa, get denied, and if the officer recommends a waiver they will let you know what the next steps are. By the way, a "240-day rule" is not relevant here. If you had a timely-filed and non-frivolous Extension of Status pending, you would not accrue unlawful presence for the entire duration that it was pending, with no time limit (even if it takes years). The 240 days thing is only about the period you are authorized to work; it has nothing to do with unlawful presence. However, in your case, Extension of Status could not be filed since you were not in the US, so you had no Extension of Status pending.

You should not have been able to get H1b if your 2-year home residency requirement has not been satisfied or waived.

There is no such thing as an "overstay waiver". Waivers are only for bans. There is a ban for accruing 180 days of "unlawful presence" and then leaving the US. You do not accrue "unlawful presence" for the entire period that a timely-filed, non-frivolous Extension of Status application is pending, no matter how long it takes.