Hagia Sofia is really a place you want to see in Istanbul whether or not you are a religious history buff. The building is so old and beautiful and it is located in a part of the city that is fun to walk around with a nice park. Maybe you don't spend all day there, but it is worth a visit.
There aren't any real signs or plaques inside, so if you want to know what's up with the place, you should bring in a guidebook or get a guide- they are available near the ticket kiosk, and they have a pretty good reputation for knowing their shit and the like.
