If i owned my own island, could i declare it a new country and make my own laws?:
It would be little differnt from owning a block of land most or all islands are either the responsibility of a near country or are called a protectorate of a country so even though you owned that "island block" you could not do as you wish.though there is a chance you could have local laws such as a town has but remember who is going to police them.