Midwife or Ob-GYN?

This is my first pregnancy and I'm at the point here I need to decide who to visit for my prenatal appointments. How do you decide between seeing a midwife or an Ob-GYN? 
I'm nervous about labor and delivery and so am looking for a supportive, positive experience. But I am not looking for a natural birth. I think I will likely have some sort of pain management medication. I would prefer only see women for my appointments and during labor because I am quite shy. And I have found a birth center that recommends both types of caregivers.  
How should I go about deciding on a caregiver that's right for me?