I'm not an attorney but I've worked in the legal profession for years. After you read the information on the USCIS website, I strongly recommend that you seek out an immigration lawyer (local, if you live in the United States) for professional advice. My boyfriend is currently going through the process of applying for his green card, and I've seen first-hand how the choice of attorney can significantly affect the immigration process. Immigration law is very complex, and you really shouldn't be seeking out advice from anonymous strangers on a travel-oriented website.