Most commented from certain category

I have a really strange problem, well perhaps its not a problem and im just a noob.

Im trying to pull posts with the most comments from a certain category.

I have a category called “Scripts”, Its category 1. I want to pull posts from that category with the most comments from the highest number of comments to lowest, maximum 5 comments.

I have the following function

function get_hottopics($limit = 5) {
    global $wpdb, $post;
    $mostcommenteds = $wpdb->get_results("SELECT  $wpdb->posts.ID, post_category, post_title, post_name, post_date, COUNT($wpdb->comments.comment_post_ID) AS 'comment_total' FROM $wpdb->posts LEFT JOIN $wpdb->comments ON $wpdb->posts.ID = $wpdb->comments.comment_post_ID WHERE post_category = '1' AND comment_approved = '1' AND post_date_gmt < '".gmdate("Y-m-d H:i:s")."' AND post_status = 'publish' AND post_password = '' GROUP BY $wpdb->comments.comment_post_ID ORDER  BY comment_total DESC LIMIT $limit");
    foreach ($mostcommenteds as $post) {
			$post_title = htmlspecialchars(stripslashes($post->post_title));
			$comment_total = (int) $post->comment_total;
			echo "<li><a href=\"".get_permalink()."\">$post_title&nbsp;<strong>($comment_total)</strong></a></li>";
    }
}

The problem is, when I look at phpmyadmin all my posts have a post_category of 0…even though I know I have a post in that “Scripts” category.

And the funny thing is, this code below in another area of the site works to show the most recent script posts.

<div id="recententries">
<span class="toptitle"><img src="<?php bloginfo('stylesheet_directory'); ?>/images/icon-comments.gif" alt="icon comments" class="icons" />Recent Reviews</span>
<ul class="list2">
<?php $my_query = new WP_Query("<strong>cat=1</strong>&showposts=5");
while ($my_query->have_posts()) : $my_query->the_post(); ?>
<li><a href="<?php the_permalink() ?>" title="Permanent Link to <?php the_title(); ?>"><?php the_title2('', '...', true, '50') ?></a></li>
<?php endwhile; ?>
</ul>
</div>

It recognises that cat=1

If I change the following sql in my hottopics function :

WHERE post_category = '1'

to

WHERE post_category = '0'

It works of course, but it pulls posts from every category.

Why are my posts not being stored with a category ID attached, yet I can pull posts with cat=1….

I know im missing something lol