I have some experience with this sort of thing, so here's my take on it.
I'm thinkin' your website is mostly going to be used for a)recruiting new members and b)information about upcoming events.
So for part A, you should really put a face on your group as much as possible. What does your group like to do? How many of each age group do you have? What is your groups history? Favorite memories? What are the backgrounds of the group leaders? Put photos up - leaders especially.
For part B, you want a simple way to find out about upcoming events - which you have, so that's good. I'd lose the scrolling announcement thing - those are a little annoying. Just have them be static. Make the calendar a prominent link on the main page or even put it on the main page. So then parents can go, "isn't there something happening this week? Oh, there it is!" and be done with it.
Have you looked into Google calendar? This thing is great - you can share your calendar with people, and parents can simply add your group's calendar to their own google calendar. And you can put a google calendar on your desktop so that it's always there in front of you. I think it's still in beta, though. But I love it.
I think you're really just concerned about general communication. Does your group have an email list? This is usually the way to go unless you have so much communication that the # of emails gets overwhelming. We use Google groups (yeah, Google is taking over the world, don't you know) for this. People are more likely to use email (passive) over a message board (which you need to actively go to). If the email gets out of hand, then switch to a message board.
Guestbooks, games, news feeds - these are just "fluff" and you don't really need them.
Hope this helps a little!