I have an interesting response to this original question.
The Archbishop of Canterburry asked Fr. Matthew the Poor (the monk in my avatar), "Will Protestants go to heaven?" To which Fr. Matthew replied, "No!" Then the Archbishop, a little turned off asked, "What about the Catholics?" to which Fr. Matthew replied, "No. And neither will the Orthodox!" Disgruntled, the ArchBishop asked Fr. Matthew, "Who then will be entering the kingdom?" Fr. Matthew said, "Everyone who is made a new creation."
So the question, as Fr. Matthew shows us, is not one of church membership, and whether that church is the one handing out the golden ticket to Willie Wonka's chocholate factory of heaven. The question is one of being recreated in the image of our saviour. So the question becomes whether you "church" or your "denomination" equips you with the necessities of salvation. Does your church give you prper theology? Does it give you sacremental union with Jesus Christ? Does it aid you spiritually.
Now, clearly, the Orthodox church does that, while the protestants do not. But that is far from saying that it is the denomination which decides one's salvation.