admin/modules -> blank!

Hi,
I'm working on setting up my Drupal account and I've messed something up! I can't get to the admin/modules page -- it just comes up as a blank page. I've tried removing the modules/gallery directory and replacing it from the tar.gz, but the error persists.

In the Drupal log, I see the following:

Message	Error in function '_gallery_init()' (gallery_base.inc:144):

    * Unable to initialize embedded Gallery. You need to configure your embedded Gallery.
...

However, I can't configure the Gallery either.

Where are the various settings stored for the module? I think I need to clear out the old, invalid settings to get things working again but I don't know where they are stored.

Jeff