We have ways of deciding that under the Constitution. The Electoral College selects the President (not "we the people") and under the Constitutionally prescribed manner have elected Obama as the next president. The question of his natural-born citizenship was raised during the primaries and many times again throughout the campaign. Lower courts chose not to even take up the issue under poor reasoning, and the Supreme Court has chosen not to review the issue any further.
Unless you are advocating some kind of insurrection against the United States, we do have to live under the laws of the land -- and abide by the rulings of the courts.