Ranking the top two-way NHL defensemen is a difficult challenge to take on. It's extremely hard to give value to all the statistics available when judging the defensive component of a defenseman's game. The offense is easy, and there are plenty of the league's top scorers who will make this list.
In order to be considered a two-way player, though, there needs to be more than just 50-point potential. We've come to realize shot blocks and plus-minus are all relative. Blocking pucks means you don't have it in your possession, and keeping it away from an opponent is a critical part of playing good defense in today's NHL.