If a person who has a different faith than yours were to hold a gun to your head and demand that either you convert to his/her faith or die, what would you choose? Let's assume that these are the only two options.
A belief is just a thought. My thoughts change all the time. Why die for a thought? I've read a few times that soldiers on the front lines often have the thought "Why am I killing these other people? I have no beef with them."
I would not risk my life or kill anyone else over a thought. Kill others because our economic system is 'better' than theirs? Because their beliefs are different than mine? Not for me thanks. Mankind has been killing each other over beliefs over millennia. I hope that will change some day.
Many of us have had to openly pretend for some spans of our lives anyways, so I'd probably default to live first.
However, I could see a situation where I would be like Socrates when there may be a more important purpose to me dying.
Also, it could be a good chance to openly illustrate how bad religion can be... although I'd hate to have to be the one under the gun to do so.
in this case they don't really care if you actually believe or not. One can not be forced to believe what they know not to be true. They in this case only want you to pretend to believe what you do not believe. So to live I would simply put on a good show.