I'm not familiar with freeserve, but can you uninstall anything called "Freeserve" in the "Add/remove programs" option of the control panel?
If not, you can install the free version of <a href="http://www.zonelabs.com" target="_blank">Zone Alarm</a> and when it asks if the offending program should be allowed to access the internet, selcet "NO" and tick the "remember this action" box. That should cure it as a last resort.
I'd also suggest a snotty call to PC World and/or Freeserve to ask what the heck their game is!
Hope it works out.