Paint a picture. Address reasons for leaving. Be clear on your reasons for leaving each position. Almost every interviewer will ask that question. If you left a job because there was a conflict in the department or with your supervisor, be brief about the conflict.
Most people don t enjoy hearing a long drawn out negative explanation.
Ask questions from the list you prepared. Asking good questions illustrates that you are already thinking seriously about the position and joining the company. Be open to compensation questions. If you are asked, be specific and precise about the base, bonus, stock options, car allowance, etc. The interviewer will usually not press you for a specific number if you answer the question in that manner.