Jae,
once you delete the threads, you would have to save by right mouse click on the netconfig tab and save.
You also need to save the view by going to view menu on the top and select save view.
Before you deleting the threads, shutdown the relevant process and threads first in the NetMonitor.
You may close the netmonitor.
Once you delete the threads and save, you can re-launch the NetMonitor.
When you launch you will see a dialog box shows as it is changed.
You will have to move around some of the threads some times.
Save it.
Hope this helps.
reggie