display issues!

Guys I am facing a display problem which I know it will be resolved with a If else statement or some condition of that kind.
I want that if user x click one of the submenus of the first query at or first display then user x will be able to see only first display layout below the while loop and if user x click in the subjects second display then user x will be able to see only the layout in the second display and not both how it is displaying now. as I said before right now the way it is working is that if user x click on one of the submenu in the first display then the layout of the first display appear and the layout of the second display as well and I only want it to show the one the user required first layout or second layout depending where the user clicked in other word "one at the time".Right now when user x click on the subjects 'second display layout' or Subjects menu then the layout of the second display appear this time not both together I guess becuase after the second query there is not more coding.

Can you help me to display one at the time e.g if user x clicked on the subject menu then only the layout of subject menu will appear or if user x clicked on the submenu menu then only the layout of the submenu menu will appear.

help please.

<?php

$submenu = false;
$cat = isset($_GET['subject']) && is_numeric($_GET['subject'])?$_GET['subject']:null;
$prod = isset($_GET['menu']) && is_numeric($_GET['menu'])?$_GET['menu']:null;
$menu_type = isset($_GET['menu_type']) && is_string($_GET['menu_type'])?$_GET['menu_type']:null
?>

//First Display
<?php 
$query = "SELECT id, submenus, image,
FROM submenu
WHERE
id= " . (int) $_GET['menu']; 
echo $query;
$result = mysql_query($query, $connection); 
 while ($content = mysql_fetch_array($result)) {
echo '<table border="0" cellspacing="0" cellpadding="0">
<td>Something</td></table>';
}
?>

// second display
<?php 
$query2 = "SELECT id, Subject, image,
FROM subjects
WHERE
id= " . (int) $_GET['subject']; 
echo $query2;
$result2 = mysql_query($query2, $connection); 
  {
echo '<table border="0" cellspacing="0" cellpadding="0" >
<td></td>
</table>';
}
?>

PHP: