need 2 combo boxes and a button to show result

What i need to do is, I need to place 2 combo boxes. by default the 1st one will be enabled and the 2nd will be disabled. First combo box will have country names and the 2nd will have state names. when a user selects the country name from the 1st combo box, the 2nd shuld then get enabled. and when a user selects the state from the 2nd combo box, there will be button next to it for clicking. on clicking the button, the values in each combo box shuld be selected and the user will be taken to a specific URL which will have the contents on current selected state in the current selected country.

thanx in advance