Hi Alan,
The Terminal command simply stopped the service from running at that time. It would be the same as finding the service in Activity Monitor and quitting. When you restart the Mac, this should start the service again and allow you to open Parallels.
Looking back through this post, it doesn't appear that have tried this already, but if you connect the printer directly to the Mac via USB, does a new printer get created in Print & Fax and if so, are you able to print? I just wonder if your issue is only when the printer is networked...
Pahu