can I stop someone from posting on my wall?

I think blocking an user only stops them from PMing you, not posting on your wall. However, you can change your settings so that only people you're a fan of, or only yourself, can write on your wall.

Go to your profile and select Edit Profile. Scroll to the bottom of the page. You'll find a drop down box. It's set to "anyone" by default but you can change it to stop people from posting on your wall. Click submit to save your changes.

Yes and no. Blocking someone prevents them from commenting directly on your wall but they can still do it if you post on any of the club walls. As I said on my last post--there's no surefire way to block people on this site. It's probably one of the least safe/secure sites I've ever been on in that way.

I'm not sure. I think you should just block the user and it will be enough.