This does not happen in FSX I get the virtual cockpit with the brakes off, so if I accidentally have my joystick throttle open the plane starts rolling down the runway.
Is this a setting fault my end, or a glitch MS end?
Starting out? Sounds like a glitch because for me so far the parking break is typically always on to start. There is the odd time it isn't in which case yah if your throttle is max the plane will start to take off. Just make sure your throttle isn't max.
Also if that happens, there isn't a plane in the game by default that goes 0-60 in 0.1 seconds. You should have lpenty of time to hammer your throttle to 0 and apply brakes to stop you.