Actually stop running commands or stop new commands from getting triggered(by voice)?
The latter is a basic function of the Recognition Global Hotkey option. If you select "VoiceAttack stops listening while keys are down", that's exactly what the hotkey will do.
If you also want to stop running commands at the same time, you'll have to map the Recognition Global Hotkey and the Stop All Commands Hotkey to the same key(combination).
Press F1 while VoiceAttack has focus to open the manual.