Use the year range option, and echo the current year using php date as the max year:
$(function(){
$('#datepicker_1').datepicker({
dateFormat: 'mm/dd/yy',
showAnim: 'show',
changeYear: 'true',
yearRange: "1939:<?php echo(date("Y")); ?>",
onClose: closeDatePicker_datepicker_1
});
});
that will set the year range in the year select list to 1939 - 2014
more details on the date picker api can be found here:
http://api.jqueryui.com/datepicker/#option-yearRange