How do I sort my topics by their date

How do I sort my topics by their date

I have a PHP website. I have a bot wich add matchs as a topic in a unique
category. And im showing that matchs with shorting by their dates. But i
have a problem i want to show matchs 6 hours before their start and 2
hours more after their start. Now im seeing the matchs until they start...
:( I need some corrections in following php code...
My website : www.macizlehd.org , www.allhdlive.com
Im showing this in sidebar
and category is : http://www.macizlehd.org/?cat=3262 ,
http://www.macizlehd.org/?cat=3133
<?php
$args = array(
'cat' => 3262,
'meta_key' => 'siralama',
'meta_value' => date("Y-m-d H:i"),
'meta_compare' => '>',
'orderby' => 'meta_value',
'order' => 'ASC', '
showposts' => '50'
);query_posts( $args );?>
<?php $s=0; while (have_posts()) : the_post(); $s++; ?><?php if($s%7==0){
if($sayi>=count($reklamlar)){$sayi=0;} echo
'<center>'.$reklamlar[$sayi].'</center>'; $sayi++; } ?><div
class="mac_baslik"> <div class="mac_tur"></div><img src="<?php
bloginfo('stylesheet_directory'); ?>/images/futbol.png" alt="Futbol maçý
izle" /><a href="<?php the_permalink() ?>" title="<?php
the_title_attribute(); ?>"><?php the_title(); ?></a></div> <?php
endwhile; ?></div></div>
Thank you for all your Answers...