Obbie,
They basically just want to hear you tell some stories about your career. I don't think i've ever met a pilot that can't talk about himself. They typically would like some examples of CRM issues and how you handled them..maybe a situation where a guy you were flying with did something that made you uncomfortable or you had to take control. Maybe some examples or irregular operations/failures or remote airport ops where you had limited support and had to do use your head and do something outside of normal to help keep things on track. Examples of good customer service where something you've done is above what's normally required of you. Maybe your handling on a disruptive pax, or a medical emergency. If you've flown in canada or in the bush i'm sure you can come up with lots of stories.
They just want to know what kind of person you are and what they can expect from you. It's really a very laid back and relaxed interview process while still remaining professional.