If you're stumped by a question, paraphrase it to give yourself time to think. Throughout the interview, think of the reporter as your guest, someone you want to make comfortable. Always offer food. Eating with people breaks down barriers quickly. Some reporters like to disarm you by getting really chummy.
Some reporters are confrontational.
Maybe you can give me some advice. Focus on your primary angle, the points that got you the interview. The best response to a tough question is a punt. Make a joke if that's at all possible, lighten up, change the focus by defusing the situation. We've recalled all the products we can find.