Hi,
I have a fresh installation of WP on my server. When I install NextGen Gallery, it installs fine, but when I click the 'Activate' button for the plugin, my site breaks and I recieve a '500 Internal Server' error.
This doesn't happen for any other plugins and all other aspects of the site work fine.
If I delete or rename the NextGen plugin folder on the website root, I can access my site again and remove the plugin.