Look at the example I gave (the link).

You need to get something like (watch the bolded stuff):

Code:
<select name=destination>
<?

fireSQLquery("SELECT Destination_ID, Destination_Name FROM destinations;");

while (there are rows) 
{
  // get one row as $Dest_ID, $Dest_name
  echo "<option value='$Dest_ID'>$Dest_name</option>"
}
?>
</select>

<?

 $selected_dest_id = $_POST["destination"];
 // do something with $selected_dest_id

?>