green card, full time student in USA, adjust status

I will assume that when you say that you worked off-campus, you worked and were paid for your employment and that you were not authorized under any form of internship or externship to work off-campus. That being said, whether you can adjust status to permanent residence in the U. S. at some later point depends upon the category, and whether there are any law changes. If you marry a U. S. citizen, illegal employment would not keep you from adjusting status in the U. S. Also if there are law changes which would allow other classes of persons who violated their statuses to adjust status, you might be benefited. Otherwise if U.S.C.I.S. was to know of your unauthorized employment, it would not allow adjustment of status and you would have to consular process your immigration papers.Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.  

That depends on how you qualify for adjustment.  Marriage to a US citizen means working without authorization will not prevent you from adjusting.