When I interview, I ask about the work you've done; if you can't give me a clear, cogent explanation of what you worked on, what it did, and how you did it, that's a negative. The rest is general conversation. If you can't bother to ask a slightly insightful question about what we, the employer, do, or how we do it, that's a negative. If you can't perform some simple personal grooming before showing up, that's a negative. I don't care if you know how to fizzbuzz, because I know you can always look it up. What I want to be sure of is that you have the ability to ask the right questions about the tasks you will be given.