[Steven Zahm]

@ Sandro Takke

I took a look at the site. It seems like you are showing hundreds of entries on a single page. Doing this is not recommended because it is like showing hundred of WordPress pages/posts on a single page. Doing this requires a lot of server resources. My guess is that you are exhausting the server resources allocated to you by your web host.

My first suggestion is to use a template which supports pagination. Any of these template do.

As for the admin server 500 error. If you changed the number of entries per page to a very large number, this error is likely being caused by running out of server resources. Can you remember how many entries per page you had set this to?