news marquee block

Hy Guys, after few times i'm returning to work on my little modified module, called "News Scroller".
The module work fine, but there is a problem, it dispaly all the content of a node, type or taxonomy, all the content of the selected nodes.
So i don't know how to add the functionality for dispaly only the publishied content, is very important.
Probably someone can help me, here is the code of my "newsscroller.module":

/***********************************************
* Module NewsScroller for Drupal created by XXXXXXXXX
* This notice MUST stay intact for legal use
* © XXXXXXXXX - all rights reserved
***********************************************/


/**
* Implementation of hook_help()
*/
function newsscroller_help($section) {
}

/**
* Implementation of hook_perm()
*/
function newsscroller_perm() {
   return array(
      'administer newsscroller',
      'view newsscroller',
   );
}

/**
* Implementation of hook_block()
*/
function newsscroller_block($op = 'list', $delta = 0, $edit = array()){
   if ($op == 'list') {
      return array(
         1 => array('info' => t('NewsScroller 1'), ),
         2 => array('info' => t('NewsScroller 2'), ),
         3 => array('info' => t('NewsScroller 3'), ),
         4 => array('info' => t('NewsScroller 4'), ),
         5 => array('info' => t('NewsScroller 5'), ),
      );
   }
   elseif ($op == 'configure') {
      return _newsscroller_config($delta);
   }
   elseif ($op == 'save') {
      return _newsscroller_config_save($delta, $edit);
   }
   elseif ($op == 'view') {
      $block = array();
      $block['subject'] = 'NewsScroller '.$delta;
      $block['content'] = _newsscroller_block($delta);
      return $block;
   }
}

/**
* Return the block configuration form
*/
function _newsscroller_config($delta) {
   $form = array();
   $form['text'] = array(
      '#title' => t('Text'),
      '#description' => t('Text, which will go in front of the ticker. You can use some HTML elemets.'),
      '#type' => 'textarea',
      '#default_value' => variable_get('newsscroller_text_'.$delta, ''),
   );
   $form['selection'] = array(
      '#title' => t('Selection'),
      '#description' => t('Method of selecting nodes to be displayed in the ticker:<br />- Node: a list of node numbers separated by commas<br />- Type: a single node type (eg page, story)<br />- Taxonomy: a list of taxonomy categories, type the term number separarted by commas'),
      '#type' => 'select',
      '#default_value' => variable_get('newsscroller_selection_'.$delta, 'node'),
      '#options' => array('node'=>'Node', 'type'=>'Type', 'taxonomy'=>'Taxonomy'),
   );
   $form['nodes'] = array(
      '#title' => t('Nodes, Type or Taxonomy'),
      '#description' => t('A list of node numbers, types or taxonomy categories which will be used for Ticker ').$delta.'. '.t('Separate each entry with commas.'),
      '#type' => 'textarea',
      '#default_value' => variable_get('newsscroller_nodes_'.$delta, ''),
   );
   $form['style'] = array(
      '#title' => t('NewsScroller style'),
      '#description' => t('CSS style attributes for the ticker area'),
      '#type' => 'textfield',
      '#default_value' => variable_get('newsscroller_style_'.$delta, 'width: 150px; height: 200px;'),
   );
   $form['item_width'] = array(
      '#title' => t('Item width'),
      '#description' => t('Width of individual ticker items in pixels'),
      '#type' => 'textfield',
      '#default_value' => variable_get('newsscroller_item_width_'.$delta, 150),
   );
   $form['item_style'] = array(
      '#title' => t('Ticker item style'),
      '#description' => t('CSS style attributes for each ticker item.  Don\'t specify height or width, though.'),
      '#type' => 'textfield',
      '#default_value' => variable_get('newsscroller_item_style_'.$delta, ''),
   );
   return $form;
}

/**
* Save the block configuration form
*/
function _newsscroller_config_save($delta, $edit) {
   variable_set('newsscroller_nodes_'.$delta, $edit['nodes']);
   variable_set('newsscroller_selection_'.$delta, $edit['selection']);
   variable_set('newsscroller_text_'.$delta, $edit['text']);
   variable_set('newsscroller_style_'.$delta, $edit['style']);
   variable_set('newsscroller_item_width_'.$delta, $edit['item_width']);
   variable_set('newsscroller_item_style_'.$delta, $edit['item_style']);
}

/**
* Return the contents of a block
*/
function _newsscroller_block($delta) {
static $loaded = false;
$eps = 50; // events per second, controls the smoothness of the ticker

   // get the parameters
   $nodes = variable_get('newsscroller_nodes_'.$delta, '');
   $selection = variable_get('newsscroller_selection_'.$delta, '');
   $text = variable_get('newsscroller_text_'.$delta, '');
   $style = variable_get('newsscroller_style_'.$delta, 'width: 100px; height: 100px;');
   $item_width = variable_get('newsscroller_item_width_'.$delta, 100);
   $item_style = variable_get('newsscroller_item_style_'.$delta, '');

   // ticker id
   $id = "newsscroller_$delta";

   // additional style information for ticker
   $style = "overflow-x: hidden; overflow-y: hidden; $style";
   {
      $pad_style="width: {$item_width}px; height: {$item_spacing}px";
   }
   $item_style = "width: {$item_width}px; height: auto; {$item_style}";

   // build the ticker contents
   switch ($selection) {
      case 'node':
         $nodes = explode(',', $nodes);
         break;
      case 'type':
         $r = db_query("SELECT DISTINCT nid FROM {node} WHERE type ='%s'", trim($nodes));
         $nodes = array();
         while ($n = db_fetch_array($r)) {$nodes[] = $n['nid'];}
         break;
      case 'taxonomy':
         $r = db_query("SELECT DISTINCT nid FROM {term_node} WHERE tid in (%s)", $nodes);
         $nodes = array();
         while ($n = db_fetch_array($r)) {$nodes[] = $n['nid'];}
         break;
   }
   $ret = '';
   $i=0;
   foreach ($nodes as $nid) {
      $node = node_load(trim($nid));

      $ret .= '<a href="/node/'.$node->nid.'"><b>'.$node->title.'</b></a><br />';
      $ret .= $node->teaser;
      $i++;
   }

   // put contents in ticker window
   $ret = '<div id="marqueecontainer" style="'.$style.'; position: relative;" onMouseover="copyspeed=pausespeed" onMouseout="copyspeed=marqueespeed"><div id="vmarquee" style="position: absolute;">'.$ret.'</div> </div>';

   // add scripts etc to page
    {
      drupal_add_js(drupal_get_path('module', 'newsscroller') .'/newsscroller.js');
    }

   return $text.$ret;
   
}
</code>

I'm waiting for your answer.
<a href="http://www.test.palermoscacchi.it/">Here</a> there is the actual result of the module, as you can see if you click, by the module, on a unpublishied node you can't read the node content.
The website is under construnction.

Thanks