combobox questions

how do i make it so when i click a link the combobox refreshes like i'm on sympatico.ca thats what my combobox says then i press home and it goes to google.ca but the combobox still says sympatico.ca??? why??

and i want it to remember the sites i visited say i type in sythe.org then i click that arrow thingy and it say sythe.org

plz help thx