Formulario select de tipos de contenidos, cck

 $form['tipos'] = array(
    '#type' => 'fieldset',
    '#title' => t('Título'),
  );
  $types = node_get_types('names');
 
  foreach ($types as $type => $name) {
    $form['tipos'][$type] = array(
      '#type' => 'checkbox',
      '#title' => t('@s', array('@s' => $name)),
      '#default_value' => variable_get('export_reset_'. $type, FALSE),
    );
  }
  return system_settings_form($form);