Hi Erin
The reason why you are able to find your messages in Google, is because Google makes an Index of the homepage about once every 3 weeks.
The only thing I can do about that is, to lock everybody out from the messageboard, so that you only have access to it, if you are a member and sign on, but I’m not willing to make precausions like that.
If you don’t like your name to appear in search engines, then don’t use it on the net, as that’s the only way to protect it.
To remove your name from Google or any other searchengine, you will have to change your public name under “my profile”, and within a couple of month it should be your new name that appears in the searchengines.
Hope this answers your questions.