Dear friend when you meet such qns be sure this is the only point to sell your personal objectives relating to the post you are competing for. The key to answer this qns is staying focused on primary objective here - selling youself as an employee. Dont describe your record collection, favourite movies, or your pet's names. Just describe what motivates your career and drives your passions.
example you may start like this( this is a mere example), I am an ambotious and self motivated, I am very happy in my life right now. I am looking to change job right now because I feel I have achieved all of the goals I set out for my self when I embarked in my previous role, 3 years ago. I have still got a strong appetite for success and I am looking for a job that will provide fresh challanges and rewards.
After such examples, be prepared for qns like What was your goals in your previous role? or how did you achieve those goals. Why dont set new goal and achieve them while in the same role? what fresh challanges are you expecting to meet in this new role? Make sure you have answers at your finger.