Links do not have a "disabled" property, so you'll have to work a bit harder.
$('#my_div').find(':input').prop('disabled', true);
$('#my_div a').click(function(e) {
e.preventDefault();
});
To re-activate:
$('#my_div').find(':input').prop('disabled', false);
$('#my_div a').unbind("click");
The :input selector Selects all input, textarea, select and button elements.
Also see http://api.jquery.com/event.preventDefault/