I get this message in the right side bar, when i switch on the menu manager plugin.

Fatal Error: Call To Undefined Function PrintAlbumMenuList() In /Usr/Home/Web/Web419780/Adambrejczak.Com/Zenphoto/Zp-Core/Zp-Extensions/Menu_manager.Php(980) : Eval()'D Code On Line 1

http://adambrejczak.com/zenphoto/

You have to enable the print_album_menu. This is used to generate the albums list in the default menu set. Alternatively you can also change that default menu set on the backend.

For the future please also state which theme you are using.

Take a look at this link: http://www.zenphoto.org/support/topic.php?id=7869#post-46646

Edit: acrylian: you beat me again