wordpress - query_post loop for first post - php

Question

I am using query_post to show a list of recent post.
And I want to give special style and html markup to the first post.
This is my current code:
$cat_args=array(
'orderby' => 'name',
'order' => 'ASC'
);
$categories=get_categories($cat_args);
foreach($categories as $category) {
$args=array(
'showposts' => -1,
'category__in' => array($category->term_id),
'caller_get_posts'=>1
);
$posts=query_posts($args);
if ($posts) {
echo '<h3><a href="' . get_category_link( $category->term_id ) . '" title="' . sprintf( __( "View all posts in %s" ), $category->name ) . '" ' . '>' . $category->name.'</a> </h3> ';
while ( have_posts() ) : the_post();
if( $wp_query->current_post == 0 ) :?>
<?php if ( has_post_thumbnail()) : ?>
<a href="<?php the_permalink(); ?>" class="thumb" title="<?php the_title_attribute(); ?>" ><?php the_post_thumbnail('post-thumb'); ?></a>
<?php endif; ?>
<h5> <?php the_title(); ?></h5>
<?php else : ?>
<?php if ( has_post_thumbnail()) : ?>
<a href="<?php the_permalink(); ?>" class="thumb" title="<?php the_title_attribute(); ?>" ><?php the_post_thumbnail('post-thumb'); ?></a>
<?php endif; ?>
<h5> <?php the_title(); ?></h5>
<?php endif;
endwhile;
} // if ($posts
} // foreach($categories

Answer 1

All you need to do is just wrap your snippet into if statement and call the_post function before while loop. By calling the_post function you will fetch first record from your queue. It should be like this:
if ( have_posts() ) :
the_post();
if ( has_post_thumbnail()) :
?><a href="<?php the_permalink(); ?>" class="thumb" title="<?php the_title_attribute(); ?>" >
<?php the_post_thumbnail('post-thumb'); ?>
</a><?php
endif;
?><h5>
<a href="<?php the_permalink(); ?>">
<?php the_title(); ?>
</a>
</h5><?php
while ( have_posts() ) :
the_post();
if ( has_post_thumbnail()) : ?>
<a href="<?php the_permalink(); ?>" class="thumb" title="<?php the_title_attribute(); ?>" ><?php the_post_thumbnail('post-thumb'); ?></a>
<?php endif; ?>
<h5> <?php the_title(); ?></h5>
endwhile;
endif;

Answer 2

Depending on what you want to style [the whole post, the title, whatever], you're going to want to identify the first post, and then conditionally output a class or whatever HTML you want for that post. The "loop" is the part of your code between the while and the endwhile. So right before the loop, put:
$is_first_post = TRUE;
then inside the while loop, before whatever it is you're trying to add styles to, put:
if ($is_first_post == TRUE){
echo (" .... THIS WOULD BE ADDED TO THE FIRST POST ONLY ....");
$is_first_post = FALSE; //this flags the next post as not being first
}