<select name="guncelle" size="1">
  <option value="a">guncelle</option>
  <option value="b">Delete</option>
  </select>

 
<?php 
$guncelle = $_POST[guncelle];
if ($adrese == ''){
 echo "Eksiksiz Doldurun Lutfen...";
}
if( $guncelle == 'a') {
$sql= mysql_query("UPDATE....")
}
elseif($guncelle == 'b'){
$sql = mysql_query("DELETE...")
}
 
 
?>