Since 1970 merger. Strike years not included (no 1982, 1987), Plus only selecting 1 team, and 1 year. Most teams won SB, a few made playoffs, and 1 (77 ATL) missed playoffs.
1986 New York GiantsIt's not so much their dominating regular season defense. They ranked 2nd behind Chicago. But they had the MVP in Lawrence Taylor, then beat SF 45-3 and Wash 17-0 in playoffs. Fielded one of the best LB corps of all time.
2002 Tampa Bay BuccaneersTony Dungy built this defense and Jon Gruden let it go wild. With Brooks, Saap and that Cover 2, they were unstoppable. They annihilated Oak in SB and brought the Bucs into glory.
1977 Atlanta FalconsThe Grits Blitz!!! Had a good Offense with QB Steve Bartkowski, but their Defense kicked ass that year. Atl went to playoffs for first time the following year, but this team set everything up. Plus the wild card wasn't set up to 1978, and they were really good for a few more years.
1973 Los Angeles RamsThe Fearsome Foursome was winding down, but this team gave up an average on 9 points per game!!! They dominated the West in the 70's, and if they had consistent QB play, could've one a SB. Team hit you hard!!