$result=dbquery("SELECT * FROM members WHERE ....;
echo "<table border=\"1\">";
echo "<tr>";
for ($i=0;$i<dbnum_rows($result);$i++) {
    $nickname=dbresult($result,$i,"nickname");
    $result2=dbquery("SELECT * FROM stat_member WHERE nickname='$nickname'",$hd_main);
    if ($approved=="Y") {
        echo "<td><input type=\"checkbox\" name=\"nickname[]\" value=\"$nickname\">$nickname</td>";
    }
    else {
        echo "<td><input type=\"checkbox\" name=\"nickname[]\" value=\"$nickname\">$nickname</td>";
    };

  };
           }
            echo "</tr></table>\n";

$i % 5 == 0