I interviewed with a history department last month, and they asked me what I was currently researchng, what I would like to work on if admitted, why I applied to that particular school, what I was looking for in a department, and what books/classes/historians have been most influential in shaping my interests. I asked about funding (it never hurts to ask), job placement rates, predictions/plans for departmental development and changes, and what made their department a great place to study. My interviewer seemed to like those questions. Well, he didn't seem to be offended, at least.