ho tenuto il tuo codice sostituendo i miei campi... forse sbaglio con ' e punti ...

Codice PHP:
$query_anno=mysql_query("Select * From democat Order by idcat") 
                                        or die("errore nella query;".mysql_error()); 
                                        for($d=0; $d<mysql_num_rows($query_anno);$d++) 
                                            { 
                                                $elenco_anni=mysql_fetch_assoc($query_anno); 
                                                print" <select name='categoria'>
                                                    <option value='".intval($elenco_anni['idcat'])."'> 
                                                    ".$elenco_anni['categoria']." 
                                                    </option> 
                                                    </select>";
                                            }