I was searching for a simple way to do this and solved it like this.

My site has ZenPhoto in a directory off the root called "zen".

I then made a custom page "home.php" which was based on "gallery.php", but customized in HTML to display the info I wanted. Then I updated the zen/index.php to point to home.php instead of gallery.php.

Then I just did a simple redirect from the default page in my root folder.