Post Install Permissions

For security reasons, after i have installed and setup my store, what should the permissions of the files be,specifically the two config files?

Also, if later on I want to add SSL, can I do it post install and if so, how do I set it up?

Set your configs to 644 or 444

You can add ssl at any time by enabling it from the admin area. If you also want the admin area to be SSL then edit the admin/config.php values for HTTPS