I have been to Saints games probably 30 times.
If you sit in the expensive seats you will have a great time and lower is not as loud. People are civilized and actually try and watch the game.
The upper deck, cheap seats, it is a entirely different world. People go to get stupid drunk, are loud and ignorant. Wear Bills gear up there and you will be mocked incessantly and a few "tough" guys might want to demonstrate hoe macho they are.
I can also tell you if it is a night game, be very careful, to the North and the east it immediately turns into some very bad neighborhoods with little light. Even Canal at night can be dangerous but there will be plenty of cops. The best thing about a football game in NOLA is the French Quarter is an easy walk. That is why NOLA is proabaly the BEST venue for a Super Bowl, everyone goes in the quarter before and after the game. I had some great times.