How To customize user account creation form
You need to use user_register_form instead of user_register.

Try using it like this :

$items['user_register_form'] = array(
    'render element' =&gt; 'form',
    'path' =&gt; drupal_get_path('theme', 'responsive_bartik'). '/templates',
    'template' =&gt; 'templates/user-register-form',
    'preprocess functions' =&gt; array('responsive_bartik_preprocess_user_register'),
);


Now create a user-register-form.tpl.php in your themes template folder.