I used to log it in USA as time spent flying under IFR and knock off say 6 mins on each end of the flight for taxiing ect, speaking to a guy today he said he logs the whole sector as IR time, anyone confirm this is the right or wrong way to do it??
I can't speak to JAA/EASA/CAA requirements for logging of flight time, but you logged your time under the CFR's in the US incorrectly.
Instrument time is time spent in conditions requiring that the aircraft is controlled strictly by reference to instruments. That one is operating under Instrument Flight Rules is irrelevant. One may operate in the clear under VFR for the entire flight and never enter instrument conditions; one is not entitled to log instrument time for that flight.
Conversely, one may operate under Visual Flight Rules and legally be in conditions requiring flight by reference to instruments for most of, if not the entire time. The FAA Chief Legal Counsel has provided several legal interpretations detailing these circumstances, such as flight between cloud layers or flight over dark terrain at night. These are indeed instrument conditions, though one has adequate visibility and cloud clearance requirements that one is not actually in instrument meteorological conditions, nor does one even require an instrument rating (in the United States). This time may be logged as instrument flight time, rightfully so, as it's conducted in conditions requiring flight by reference to instruments. Even by someone without an instrument rating, and even when not operating under IFR.
Log the time spent actually flying by reference to instruments, when you have no other means by which to control the aircraft, as instrument time. Do not log time spent under IFR as instrument time, as it really has nothing to do with logging instruments.