The nondigestable option allows you to disable immediate sending of messages for your list. Set this to No if you wish to allow digest delivery only.
The msg_header and msg_footer options allow you to add a header or footer (or both) to each message sent out. By default, messages have the Mailman list's name (real_name), the address of the list, and a link to the listinfo page for the list are added to the bottom of every message.