Mike, I'm sure Dad will reply soon, but I will help a little. Make an educated guess of which discussion you should post your topic. You can even state "I'm not sure it belongs here" and the moderators will move it if they need to. From that point, you can subscribe to the thread to get email notifications if someone has replied to the original thread. Hold your cursor over the different icons in the threads to see what each will do for you. When responding to a topic, even if it is your own, just click on the "reply to topic". You can also "edit" your own topics and it will bump it back up to the top of the discussion line. people will then see that you "Edited: your post. Hopefully this doesn't confuse you more.
I think there is also a discussion area for problems you may be having with the site, and I think the Moderators and Mom and Dad monitor that quite often.