You shouldn't need to reset. All settings can be done using one of the setup apps. If you can't connect, use one of the USB apps. Either Windows or Mac.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .