domain name server for local resolutions

i have a vsat link with an isp in Denmark,my location is Lagos,Nigeria.i plan to register a domain name of my own so that i can have packets resolve thru a local dns rather than thru d isp’s dns which has made d link quite slow because of distance thus the usual high reply time of about 580ms.my confussion’s are:1.which ip address will i attach to d dns i want to register?2.how does d new settings affect that which is already configured in d IPSAT equipment from d isp?3.how will i configure thedns server to act as my packet resolution server?4.which role will my isp play in all this? i hope i can get good explanation asap.i would also like to know how i can go about registering the dns and what would be required of me.