Snippet to see what content types are used by your views in your Drupal site. Create a file with this content, then execute it with `drush php-script`.

views_content_types.php

<?php

$rows = array();
foreach (views_get_enabled_views() as $view) {
  if ($view->base_table == 'node') {
    foreach ($view->display as $display) {
      if (isset($display->display_options['filters']['type'])) {
        $rows[] = array(
          sprintf('%s (%s)', $view->human_name, $view->name),
          $display->display_title,
          implode(',', array_keys($display->display_options['filters']['type']['value']))
        );
      }
    }
  }
}
drush_print_table($rows);