I’ve written a WordPress plugin to generate a browser for all the NextGEN Gallery albums that you have. You can see it in action on my photos page.

To install you must be using the NGG plugin (obviously) and then just place ngg-album-browse.php in your wp-content/plugins folder. Activate it, then you can use the following shortcode to insert it in a page or post (without the spaces):

[ albumbrowser ]

You can also display albums in a random order:

[ albumbrowser order="random" ]