How can I suppress the "terminate batch job" in cmd.exe

The behaviour is implemented in the cmd.exe source code, and isn't possible to turn off without modifying cmd.exe. However you can modify cmd.exe to not show the message.

At this site, I finally found an effective solution:

script.cmd < nul

To not have to type this out every time I made a second script called script2.cmd in the same folder with the line above. You may want to reverse the names. Works for me, but tested so far on XP only.