1.is it moral within Christianity to use your religious beliefs to direct what business choices you will make?

I would say it's mandatory, really. Is there any part of one's life that one's moral code should not extend to? and doubley so in Christianity, where the believer is himself assumed to be the property of God, brought with the death of Christ.

Case in point; A Christian should not be, say, a hitman or prostitute, and when Jesus saved the woman caught in adultery, he ended the encounter with "go and sin no more."

As for moral or immoral, we come to a question: What does that even mean in a pluralistic framework? Who or what is the authority? The consent of the community as a whole? The laws as written by government officials? Generally speaking, Christianity interprets moral to mean "in agreement with God and his laws." If I wanted to be specific, I would quote the two greatest commandments in Matthew 22:

36 “Teacher, which is the greatest commandment in the Law?”

37 Jesus replied: “‘Love the Lord your God with all your heart and with all your soul and with all your mind.’ 38 This is the first and greatest commandment. 39 And the second is like it: ‘Love your neighbor as yourself.’ 40 All the Law and the Prophets hang on these two commandments.”

But, again, this is interpreted in the framework of the laws of God and obedience thereto. Jesus could save his people on the cross because he perfectly obeyed God's law, and likewise, death entered into the world because the first man and woman disobeyed God by eating the forbidden fruit. That is, obedience to God, and thus, morality, cannot be simply re-conceptualized to mean "whatever I happen to like or want to do". Christian love is not something that should be oversimplified to mean "that person was mean to me, and therefore they aren't loving!" Case in point: exhibit 1 and exhibit 2.

So, the question is really this: where does the claim that it would be immoral to refuse such service get it's authority?

(and so I might defuse the euthypro dilemma now and not later: I quote C.S. lewis):

Such people put up a version of Christianity suitable for a child of six and make that the object of their attack. When you try to explain the Christian doctrine as it is really held by an instructed adult, they then complain that you are making their heads turn round and that it is all too complicated and that if there really were a God they are sure He would have made 'religion' simple, because simplicity is so beautiful, etc. You must be on your guard against these people for they will change their ground every minute and only waste your time. Notice, too, their idea of God 'making religion simple'; as if 'religion' were something God invented, and not His statement to us of certain quite unalterable facts about His own nature.

Moving on:

2.Does the government have a right to tell people how they must interpret their religious beliefs under penalty of not being allowed to run a business without being in contradiction with their religious views?

And again, the question must be asked: where does a governing body get authority? if we speak of the pluralistic society, is it the will of the people? The monopoly of force? Indeed, if we're going to seriously remove God from the picture here, then we have only one real answer, and it is because the government can do as it wishes - a monopoly of force enabled a government, whether run by the people or by a tyrant, to act forcefully upon the country. It is mostly irrelevant whether the government is "right" or "wrong", since these terms fade into obscurity in the face of the simple fact that in a framework with no legitimate authority, the law of the land is that Might makes Right.