Example for to disable a form part in add page or add story
its verry simple just make a module for it or add this to a existing modulefunction my_module_form_alter ($form_id, &$form, &$form_state)
{
#if page only
#if (isset($form_id['type']) && page_node_form' == $form_state);
if (isset($form_id['type']) && $form_id['type']['#value'] .'_node_form' == $form_state)
{
#var_dump('<pre>' ,$form_id, '</pre>');
$form_id['menu']['#title'] = '';
$form_id['menu']['#type'] = '';
$form_id['menu']['weight']['#default_value'] = -50;
$form_id['menu']['#collapsible'] = FALSE;
$form_id['menu']['#collapsed'] = FALSE;
$form_id['comment_settings']['#access'] = FALSE;
$form_id['attach']['#collapsed'] = FALSE;
$form_id['body_field']['format']['#access'] = FALSE;
$form_id['path']['#access'] = FALSE;
}
}