Changing automatic freight zone

[Nss2]

Hi i would like to change what freight zone is used by default in my prestashop. Right now i have two different zones and the one that is the most expensive and furthest away from me is the one that is set as default, this changes when customers log in but i think that sometimes it can scare customers away so that they never register at all.

 

Any help would be greatly appreciated, even if you do not know how to change the default setting i would like some info on how to perhaps hide the freight cost until the customer has logged in.