With your mouse, click on "Servers" from the top (as shown below).

Both Mail Servers should be set to net.bluemoon.net
Make sure you change the "username" to YOUR login name.
The "Mail Directory" is a directory on your hard drive. This is where your mail goes to. You should not have to edit the path at all. This is the same with the "News RC Directory."
Click the "OK" button to move to the next step or Click the "Cancel" button to go back a step.