You may prefer not to have numbers in front of Article titles in Category list view. Joomla 1.5 doesn’t provide functionality to remove this.
This can achieved via a simple core hack.

• Open file:
  components/com_content/views/category/tmpl/default_items.php
• Scroll down to line 69 and delete (or comment out) following code:
  <td align=”right”>
        <?php echo $this->pagination->getRowOffset( $item->count ); ?>
  </td>

Warning: This is a core hack. Any Joomla update may overwrite your changes.

Backup any files you are changing and document the changes.