This is one of the few things in the JAR's that are pretty simple.
According to JAR, you can log as flight time, the time from when the helicopter moves under its own power for the intention of flight until it comes to rest at the end of the flight and its rotors have stopped.
I disagree. Look up JAR-FCL 2.001 and look up Flight Time Recording for helicopters and planes. Unless of course you can direct me to where it states what you have written?