Exclude category on the homepage

I’ve been doing some editing to the way the homepage looks and making it so each category shows 2 posts on the homepage. What I want to do is to be able to exclude a few of the categories on the homepage though so not every one is represented.

<div class="home-wrapper">
    <div class="home-left">
        <!--Begin recent post-->
         <div class="home-post-wrap">
<?php
//for each category, show 3 posts
$cat_args=array(
  'orderby' => 'name',
  'order' => 'ASC'
   );
$categories=get_categories($cat_args);
  foreach($categories as $category) {
    $args=array(
      'showposts' => 2,
      'category__in' => array($category->term_id),
      'caller_get_posts'=>1
    );
    $posts=get_posts($args);
      if ($posts) {
        echo '<div class="cat-title">' . $category->name.'<div class="cat-title-right"> <a href="' . get_category_link( $category->term_id ) . '" title="' . sprintf( __( "View all posts in %s" ), $category->name ) . '" ' . '>More...</a></div></div>';
        foreach($posts as $post) {
          setup_postdata($post);
		  ?>
		  <div style="clear: both;"></div>
         <h2 class="titles"><a href="<?php the_permalink() ?>" title="<?php printf(__('%s','PureType'), get_the_title()) ?>">
                <?php the_title(); ?>
                </a></h2>
				<?php include(TEMPLATEPATH . '/includes/postinfo-create.php'); ?>
				<div style="clear: both;"></div>

			<?php $width = 70;
				  $height = 70;

				  $classtext = '';
				  $titletext = get_the_title();

				  $thumbnail = get_thumbnail($width,$height,$classtext,$titletext,$titletext);
				  $thumb = $thumbnail["thumb"];  ?>

			<?php if($thumb != '') { ?>
				<div class="thumbnail-div">
					<a href="<?php the_permalink() ?>" title="<?php printf(__('Permanent Link to %s','PureType'), get_the_title()) ?>">
						<?php print_thumbnail($thumb, $thumbnail["use_timthumb"], $titletext, $width, $height, $classtext); ?>
					</a>
				</div>
            <?php }  ?>

            <?php truncate_post(250) ?>

			<div style="clear: both;"></div>
          <?php
        } // foreach($posts
      } // if ($posts
    } // foreach($categories
?>
        </div>
        <!--End recent post-->
    </div>
    <div class="home-right">

        <?php if ( !function_exists('dynamic_sidebar') || !dynamic_sidebar("Homepage") ) : ?>
        <?php endif; ?>
    </div>
</div>

Really appreciate it if someone could help me out.