Will my work for the UN in Iraq be counted as residency in the US ?

It is best if you meet with an attorney to consult with, but my first answer would be " no."

You should talk to your company's attorney. A change in the job location, is a significant change.

All it means is that you need to provide your medical exam. Until you get a written notice from USCIS approving your case, nobody can tell you if...

How can we get married?

You need to show that you met him in person within the last 2 years prior to submitting your K1 petition.

What action can i take against him, so that I can get my salary back from him?

If your employer does not pay you at all, not by cash, not by check, than you have a valid claim against the employer.

TPS for F1 student

Well, you will lose your F1 status. You will be in TPS status, but that is not really a status to change it to any other or adjust status based on...

Do I need to file EAD for my son (aged 8) as part of my I-485 application?

Your son, obviously, will not be working. But an EAD will help him to get a Social Security number.

Affidavit of support I864

An immigration would have to file a petition to enforce the contract in a Federal or State court.

Does 30/60/09 day rule apply to B-2 to E-2 change of status?

The process of status change is always relies on facts specific to one's case. Work with an attorney to avoid issues.

Would the history of overstay in the U.S. affect the visa obtaining process?

Overstay in the US should not affect your eligibility for visa to UAE or Canada, unless the overstay somehow will be used against you in connection...