I liked the Cowboys in the 70s, primarily because of Staubach. They weren't my favorite team, as I was a Raiders fan [and a Bengals fan unless they played the Raiders], but I rooted for Dallas in the NFC and in the Super Bowls, especially against the Steelers.
I've generally rooted against Dallas ever since Jerry Jones bought the team. I still root for them when they play the Steelers however.