Actually I think the first tie-breaker for conference is head to head. But that's not applicable here because all three teams, the Giants, Saints, and Seahawks, don't play each other. I know the Giants played the Seahawks and we play the Giants but we don't play the Seahawks so you can't use head to head. So then it goes to conference records.
Remember this is how we got left out of the playoffs in 2004 when there was a three way tie between the Saints, Vikings, and Rams. The Vikings and Rams got in even though we beat the Rams. Had the Vikings played the Rams we would have gotten in but because they didn't it went by conference records and we missed the playoffs. That's why if you're going to lose games you want it to be games against the AFC.