The best thing the Giants could do is work out a trade with the Bills....say the #2 for #12, #22, 2nd, 3rd.
Then spin around and trade the #12, 2nd, 3rd to move up to ~7-8 spot IF either Bradley Chubb or Quentin Nelson are available still.
Giants would have a guy that would have been worthy of a #2 pick, but would have the #22 in the 1st as well. It would be a serious miscalculation not to cut a deal with Buffalo, who has to be beyond desperate to move up for a QB.