I think this is about it:
<html>
<head>
</head>
<table border="0" cellpadding="0" cellspacing="0" width=100%>
<td width = "10%" valign="center" align="center"><p>Product</p></td>
<td width = "10%" valign="top" align="center">
<?php
$item = $_GET;
if ($item == "")
{
$item = 1;
}
?>
<select onChange="window.location='ban.php?product='+this.value" >
<?php
$product = array(
"",
"PC",
"Scanner",
"Printer",
"Monitor");
for ($i = 1; $i <= 4; $i++)
{
?>
<option value="<?=$i?>" <? if ($item == $i) { print "SELECTED";}?>> <?=$product?></option>
<?
}
?>
</select>
</td>
<td width= "50" valign="middle"><img src = "<?=$item?>.gif" width="32" height="20">
</td>
</tr>
</table>
<hr>
</html>