Marcia,
Best wishes with it - I know how hard it could be to get a forum together - could I ask what the dog tags would be in reference to?
The start page of the forum is excellent work. The navigation is all laid out for the user in an immediate viewable location. I like the drop down that asks for how long you want to be logged on.
Is that cookie based, meaning does the cookie also get destroyed when the user gets logged off automatically?
To be able to hide the header is advantageous in that many people do not want to be distracted by the same information and want to concentrate on the core reason of going to a forum - information.
The social buttons are cool as mentioned.
Personally not a fan of black/gray sites but it is clean and straight forward and a well designed start.
Regards,
Rob