A friend's sixth-grade daughter has been using Limewire to share music online. Recently, the PC slowed to a crawl. During the process of removing a significant amount of malware, I determined that the young lady was using Limewire. In the Limewire folders, I found over 9,000 pornographic movies. It appears that Limewire is granting access to others to use the PC in a file sharing environment as storage for uploading and downloading unwanted files. Besides removing Limewire from the system, is there some way to configure Limewire to not allow access to the PC from unwanted users? What security measures should be taken to keep this from happening again?

Thanks!