evet aynı html koduna baktığımda browserden şunu verio
<HTML>
<HEAD>
<TITLE>PHP'de Formlar</TITLE>
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-9">
<meta http-equiv="Content-Type" content="text/html; charset=windows-1254">
</HEAD>
<BODY>
<BR>
<SELECT NAME="kategori"><?
while ($row = mysql_fetch_array($result))
{
?>
<option><br />
<b>Notice</b>: Undefined variable: row in <b>C:\wamp\www\deneme5.php</b> on line <b>25</b><br />
</option>
<?
}
?>
</SELECT>
</BODY>
25. satır kodtaki
<option value="<?php echo $row[0];?>"><? echo $row[0];?></option>
satırı
</HTML>