Working as a Program Director in radio for years now, I have conducted countless interviews. Believe it or not, most of the questions I ask are not even related to broadcasting. The way I see it, your audition tape, and resume should be able to tell me more about you that you could in an interview. Sometimes people tend to lie a little bit in interviews, but whatever is on your air-check tape will not lie.
Most of the questions I like to ask are to try and find out what kind of worker you will be. I try to weed out all of the people that seem to be slackers, then invite a few of the top candidates back for a second interview.
The think you need to remember most is to be on time for your interview. That will be the first impression the interviewer will make of you, and you always want to make a good first impression.
One other thing, Here is an inside tip, we in the business do not like to be called Disk Jockeys. A disk Jockey is somebody that works in nightclubs, and has to hustle for wedding gigs and things like that. While there is nothing wrong with being a Disk Jockey, We like to call ourselves Air Personalities, or Air-Talent. It is more of a "Profession" being on the radio apposed to just being a DJ.
I wish you the best of luck with your interview.