Showing the_excerpt based on category

I have a homepage of my website that I pull in the latest two post from my wordpress blog using the_excerpt. I want to be able to write less important post on my blog that don’t show on my website homepage. Is there a way to control what will show on the homepage? For example could I add something to my code that will prevent it from showing post if that include a certain category or something. I will post the current code I have below. Thanks for the help.

define(‘WP_USE_THEMES’, false);

require(‘./blog/wp-load.php’);

query_posts(‘showposts=2’);

?><?php while (have_posts()): the_post(); ?><?php get_the_image( array( ‘the_post_thumbnail’ => true , ‘default_size’ => ‘medium’ , ‘height’ => ‘200’)); ?>

<span style=”width: 40%; color: #DBAA56; font-weight: bolder;”><?php the_title(); ?>
</span>
<div style=”clear: both; padding-top: 1px”>
<?php the_excerpt(); ?></div>

<p>Read more…</p>
<?php endwhile; ?>