<?php if(have_posts()) : while(have_posts()) : the_post(); $counter++; // add +1 to count for each post ?>
<div style="float:left;" <?php post_class(); ?> id="post-<?php the_ID(); ?>">
<div class="blog-thumb"><a href="<?php the_permalink(); ?>"><?php the_post_thumbnail('featured-post-thumbnail'); ?></a></div>
<h1><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h1>
<?php if($counter===1) {the_content();} else {the_excerpt();}?>
</div>
<?php endwhile; ?>
<div class="navigation">
<div class="next-posts"><?php next_posts_link(); ?></div>
<div class="prev-posts"><?php previous_posts_link(); ?></div>
</div>
<?php else : ?>
<div <?php post_class(); ?> id="post-<?php the_ID(); ?>">
<h1>Not Found</h1>
</div>
<?php endif; ?>