Adding Categories to Pages

I know there are plenty of post around this subject, but can’t get it to work, I’m not a developer, but I follow directions well if I see it. I want to show category id = 12, I inserted <?php query_posts(‘cat=12’); ?> before “the loop”, but can’t get it work. Any ideas? Thank you in advance.

<?php
/**
 * Template Name: Learn
 *
 * The blog page template displays the "blog-style" template on a sub-page.
 *
 * @package WooFramework
 * @subpackage Template
 */

 get_header();
 global $woo_options;
?>      

    <!-- #content Starts -->
	<?php woo_content_before(); ?>
    <div id="content" class="col-full">

    	<div id="main-sidebar-container">    

            <!-- #main Starts -->
            <?php woo_main_before(); ?>

            <section id="main" class="col-left">
<?php query_posts('cat=12'); ?>
			<?php get_template_part( 'loop', 'blog' ); ?>

            </section><!-- /#main -->
            <?php woo_main_after(); ?>

            <?php get_sidebar(); ?>

		</div><!-- /#main-sidebar-container -->         

		<?php get_sidebar( 'alt' ); ?>       

    </div><!-- /#content -->
	<?php woo_content_after(); ?>

<?php get_footer(); ?>