mjoel wrote:
Bingo !!

global $xoopsDB;
$sql = "SELECT uid, uname, user_avatar  FROM ".$xoopsDB->prefix("users")." WHERE level > 0 AND uid NOT IN (1) AND user_avatar <> 'blank.gif' ORDER BY RAND() LIMIT 10";
$result = $xoopsDB->query($sql);
while (list($uid, $uname,$user_avatar) = $xoopsDB->fetchRow($result) )
{
echo ".$user_avatar."'alt='Avatar'>";
echo ".XOOPS_URL."/userinfo.php?uid=".$uid."'>".$uname."";
}

admin is not included - uid NOT IN (1)
user with no avatar not included - user_avatar <> 'blank.gif'
show 10 random user RAND() LIMIT 10