Thanks for the response Eric. I defintely don't want to run the server with auto-login on. However, the utilities which allow you to run a "normal" program as a service still work.
For any interested, the instructions are at: http://support.microsoft.com/kb/137890
The only difficult part is that if you want to make changes to the configuration. To do so, you'll need to stop the service, then run NZB-TV normally to access the GUI and make the configuration changes. Afterwards, you'd need to restart the service.
I guess as long as it works that's all that matters. :)