Eagles have a very fast D, and their DBs are the best in the game. Colts also have good speed. But if you're willing to give up a bit of speed, I would go with the Ravens for stopping the run. I also like the Vikings, they've got a solid run D, and if you can pressure the QB with the awesome D-Line, you can force turnovers on passing downs. It all depends on your style of playing. Cowboys are a good all around defense too, which can help if you are a new player. But if you are a serious top-tier player, you can dominate all aspects of the defensive game with any of these teams. Good luck!