Tog efter din kod, den va enkel att förstå
function writeParents($fid) {
$check_parent = mysql_query("SELECT parent FROM forums WHERE id = {$fid} && parent != 0");
if(mysql_num_rows($check_parent) == 0):
return false;
else:
$new_parent = mysql_result($check_parent, 0, "parent");
writeParents($new_parent);
echo " - <a class='orange' href='".ROOT."forum.php?id=".mysql_result($check_p arent, 0, "parent")."'>". mysql_result(mysql_query("SELECT name FROM forums WHERE id = '".mysql_result($check_parent, 0, "parent")."'"), 0, "name")."</a>";
endif;
}