1) You can change the order the galeries are displayed in by editing the order by statement on the choosegallery.php page;
find the recodset code:
$result_gallery = mysql_query('
SELECT *
FROM pg1_gallery
ORDER BY id ASC');
and change it to:
$result_gallery = mysql_query('
SELECT *
FROM pg1_gallery
ORDER BY title ASC');
2) There is no multiple delete option in power gallery, I will add a feature request for this to be considered in the future.