Every organization has a market to grow, a customer to woo and competitors to beat. Be sure you understand the big picture by identifying those three elements. Understanding those will make it easy to figure out the rest: why they're in business, how they make money, what's most important to their growth. Prepare some questions that relate to these big picture items, and you'll show that did your homework and maybe even gained some insight.
Then turn your focus to understanding what the job is and how it fit's in to what the organization as best you can. Businesses are complex organizations and all are organized differently. Ask a specific question that shows you are doing your best to understand the nature of what your accountabilities would be in the role, and how the role contributes to the overall success of the business unit or organization. You likely won't get it exactly right- and that's ok. Interviewers don't expect people to understand what happens exactly in the role, but they will appreciate that you tried.
Lastly, focus on yourself and your interest in this job. What appeals to you about it? What makes you think you'll be good at it? Why do you want it? Its way more important in any interview to be able to discuss these things authentically than it is to list your strengths and weaknesses.
And really, if you don't have a good answer as to why you want this job, or why you think you'll be good at it- are you sure you want to go to the interview?