Free JavaScript Country/State Select pluin,this is the simple DEMO
<script src="country-state-select.js"></script>
Select Country (with states):
<select id="country"></select>
State:
<select id="state"></select>
<br/>
Select Country (without states):
<select id="country2" name="country2"></select>
<script language="javascript">
populateCountries("country", "state");
populateCountries("country2");
</script>