Query_posts Killing my website (memory killer)

Hello every one, I am a WordPress Develper, and I have worked in 17 languages. I am working on this website that requires that each language will be able to display a series of Postings from its anual series of studies, see: http://www.melechyisrael.ca/torah-english/

Hre is the the code I use to fetch each category:

[code]

<?php global $post; $myposts = get_posts('numberposts=20&offset=0&category=6998'); foreach($myposts as $post) :?>
<li class="arch-th">"><?php the_title(); ?>
<?php endforeach; ?>

[/code]

There is 60 different categories. But they kill the site (they use more then 32 megs of ram every time they are accessed. Any ideas on how to reduce the server’s load.

This is the only way I thought I could show all categories from that section. Any ideas? any pointers?

Thanks,