I applied and interviewed for the VALOR student nurse position at the VA, and that is the summer job that I have now. My understanding is that the VA has panel interviews, meaning there will be about four or five people interviewing you. They do have set questions that they ask, I heard somewhere you can get the list online but I am not sure.
It's hard for me to know for sure what questions they will ask of you because my position was a student position and I don't know if they would ask the same questions for a nurse residency. Just prepare like you would for any interview, go over your nursing process, know your own strengths and weaknesses and be able to explain them succinctly and confidently. Oh! And think about why you want to work for the VA. Know about the VA. Good luck!