It's because your script

  $('#CCMethod').change(function(){
      if ($(this).is(':checked')) {
        $('#CCPay').fadeIn('slow');
      } else {
        $('#CCPay').fadeOut('slow');
      }                   
    });

is running before #CCMethod is declared. Wrap it in a doc-ready:

$(function() {
    ('#CCMethod').change(function(){
      if ($(this).is(':checked')) {
        $('#CCPay').fadeIn('slow');
      } else {
        $('#CCPay').fadeOut('slow');
      }                   
    });
 });