POP Accounts: This will backup the account settings for all of your POP mail addresses.
Forwarders: This will backup all the forwarders created by you.
Autoresponders: This will backup all autoresponder accounts and the message content of the autoresponders.
Vacation Messages: This will backup all vacation message settings and the vacation message itself.
E-mail Settings: This will backup all filters and the catch-all e-mail address.