I would start off on a light foot with the person you're interviewing. Ask some questions to learn a little about their personality. Maybe ask them about their schooling and what kinds of things they do in their spare time. Go into the more technical questions after you get a feel for their personality. Ask what kinds of experience they have with web programming, and if they have a site of their own. Ask about their HTML and Javascripting ability. I would basically look at the job description and pick the most important aspects of the job and ask them about those.