Ephesians 4:25 tells us to put away all falsehood and speak truth while being imitators of God and walking in love. Our motivation, again, is not the winning of the argument, but the soul of the unbeliever. But don't be deceived, having the discussion, debate, argument--whatever term you apply to it--it must happen. It is through the dialogue that God will plant seeds of truth or accomplish His redemptive ends altogether. We don't know, but we must not avoid the worldview discussion.
When Paul addressed the people at the Areopagus (Acts 19:22-32) he made known to them what they had identified for themselves as unknown by proclaiming Christ. Similarly, with meekness and gentleness we are called to give an answer for the hope we have in Christ, making a defense to anyone who asks. This may involve destroying arguments (in love, of course) and any opinions raised against the knowledge of God (1 Cor 10:5).
if there is a willingness to discuss religious beliefs with unbelieving friends, the worldview approach which questions their source of knowledge and basis for belief and their justification of morality (right and wrong) is a great place to begin. What it will reveal is that people cannot live without absolute truth and that they cannot account for any knowledge within the framework of their own worldview. Borrowing from Christianity philosophically is the only way people actually live, and we can show this to be the case if we are willing to enter into a ministry of apologetics in our individual relationships. Apologetics isn't an academic exercise, it is a necessary ministry in our anything-goes pluralistic culture.