ORDER BY has another clause called "ASC" and "DESC" which take whatever column you specify (like "id") and alphabetically order it.
<?php
mysql_query('SELECT * FROM `table` ORDER BY `id` ASC');
?>Also, don't use double quotes (") when working with strings as it takes longer. Second, make sure to sanitize your sql (mysql_real_escape_string) or you WILL get hacked! Third, don't set mysql_query() to a string - just do something like:
<?php
$query = 'SELECT `name`, `desc`, `poster`, `id` FROM `topics` WHERE `id` = \''. mysql_real_escape_string($_GET['tid']). '\' ORDER BY `id` ASC';
//If there is a problem
if(!mysql_query($query)) { die 'MySQL Error:'. mysql_error(); }
//on with the code
?>