Display latest post

I’m very new to WordPress so this is probably a very very simple problem.

I want index.php to display my latest post.

This is what I have so far:

<?php if (have_posts()) : ?>
<?php while (have_posts()) : query_posts('p=1'); ?>

<span id="a1"><?php the_time('F jS, Y') ?></span><br />
<h3><?php the_title(); ?></h3>
<br />
<?php the_content(); ?><br />
<?php the_tags('Tags: ', ', ', '<br /><br />'); ?>
<a href="<?php bloginfo('rss2_url'); ?>" class="rss">Subscribe!</a><br /><br /> Posted in <?php the_category(', ') ?> | <?php edit_post_link('Edit', '', ' | '); ?>  <?php comments_popup_link('No Comments »', '1 Comment »', '% Comments »'); ?>

<?php endwhile; ?>

<br /><span class="alignleft"><?php next_posts_link('&laquo; Older Entries') ?></span>
<span class="alignright"><?php previous_posts_link('Newer Entries &raquo;') ?></span>

<?php else : ?>

<h2>Error</h2>
<br />Can't find anything like that.
<?php include (TEMPLATEPATH . "/searchform.php"); ?>

<?php endif; ?>

This only works in displaying the title, date and tags of the post. It won’t display the content.

Any help appreciated.

Thanks