Depends,
if you entered the country LEGALLY but overstayed your visa, then you can get legal residence without leaving the U.S.
if you entered the country ILLEGALY, then you CANNOT get legal residence in this country, you would be required to travel to the U.S. embassy/consulate of your home country.
It's not illegal.
Once you are officially married to an American citizen, you can not be deported from the country, unless you engage in a criminal offense.
You do not need to be married any particular length of time to apply for US residency. Once you are married to a US citizen you can apply for residency right away. The process takes about 6 months to complete.
If you are a US Citizen, legally divorced or widowed, you can request permanent residency for your spouse, regardless of how you gained your citizenship.
It is until you have registered as a married citizen in America.
No, both my marriages were like the one you described. They will get their residency regardless.
After 3 years of legally married with a Romanian citizen, you can apply for a parmanent residence (Romanian Passport).
You must comply with the visa and marry her within the 3 months that is specified! Your marriage in another country doesn't effect the visa. That is your secret, as far as INS is concerned. Get married and apply for permanent residency.
It depends on the extent of time you have been a resident. If you are permanent resident, you will not lose your visa. However, if you are on a work permit issued due to marriage to a US Citizen or if you are on a temporary resident permit (this is given while awaiting the permanent card), these can be revoked and the person sent back to their country of origin
She will still need to be sponsored by the spouse (who is an American Citizen) and apply for residency first. Once permanent residency is granted, she has to wait (I believe it's approximately two years) to apply for citizenship.
No. Neither will automatically become citizen of the other country.
If you get married in another country, you have to have a ceremony in America. You should get married in the state you live in to meet residency requirements.