That's what I thought zazen was supposed to be, but that's not how they're practicing it. When using the "counting your breath" approach, as I always had, they now insist that I start over whenever I hear something external, instead of of just noticing it quietly and going on counting, the way I always had. (Which works, and *does* create a certain amount of awareness.)
Their way, I never get to count past "1," and it drives me crazy! I eventually just get disheartened and stop.
I trained in the breath counting method in a Rinzai zen dojo (I believe this method is used in Rinzai not in Soto?), and they never insisted on that. That strikes me as being counterproductive.
As Mary intimated, I think you really have to find your own meditative doorway. It may be zen or it may be something else. I would just give the advice that you should initally gain a grounding in an authentic tradition.