I have already posted this in another thread, but I think this will help other guys too. I saw today few people picking up visa with me for DV category, unfortunately I guess none of them are registered here, anyway
About my interview, first they asked me to pay for the interview fee, so paid at the cashier counter then after few wait I was asked to submit the original documents and then they asked me for the fingerprint and after few wait I was called for the interview.
First they ask me for the language and I said I am comfortable with English and did my Interview in English (you can do it in your native language, doesn't matter, a lot of people did it in their native language and I saw them today picking up Visa) and they asked me just about my education, what do you do now? and anyone of your family members or friends in USA, and just these types of question and around it, so it's not that scary as we used to think. Just go with the flow and answer what they ask.
And best of luck to all of you reading this.