Different firms ask different questions, some firms ask general stuff like "tell me about yourself, while others ask "tell me about a time when you went against the grain".  I recommend getting an interview book and learn how to answer their questions how they see them correctly answered, in other words tell them what they want to hear.

Yes, be honest but not too honest.  To me interviewing is a big game much like how others persive me at work.  I knock interviews out of the park since I know exactly how to word my responses and how to take something negative and turn it into something positive.  If you treat the interview like a game and kinda of fluff yourself you will do great.  Though, when it comes to interviews my communicaiton skills are excellent so its a little of a different perspective than lets say someone who literally persperates during the interview and is nervous.  You must come across as confident, clear, knowledgeable, and prepared.  If you put on a show during the interview and you actually fullfill what you were able to market then you should get the job.  I can only think of a handle full of times where I interview and didn't get extended an offer.

As short as I can be, "give them what they want"

Well, when in your first year you can kind of tell who is going to be there another year.  When I worked in PA I could always tell for some reason (gut feeling) when someone was going to be asked to pursue other opportunities.  I actually had a first year that was all excited about his first job out of school.  Needless to say I actually enjoyed working with him a lot, I taught him a fair amount but he was on my engagements roughly 1/4 of the time but from the actual time that he was he always praised me on how I manage the client relationship so well and that I give him the guidance needed, etc.  But, for some reason I could just tell that they were going to cut him as I realized that he required additional time from a senior's position.  He was actually going to purchase a new car during busy season and I told him to just wait it out and that when I first started I bought me a new BMW but wished I just kept my old car given how you just wear the car down during auditing for the amount of travel you do, so he pushed off the purchase and two months later he was let go.  He had personality conflicts with most of the other seniors and managers but with me he got along and of course I would hear what others always talked about.  So I wouldnt' just classify one mistake as being a mark on your record its just after being in PA for a little while you can just tell who they want to stick around, who they abuse (people with H1's) and people who they want out. 

Once again, I always say that majority of people 99% leave PA, so get the best name on your resume for the first 5 years and leave for a better paying job with less hours.  View PA as an extension of Grad School, pay your dues for a couple years and leave <quote from a CFO on one of my first engagements> :)