Right, basics.
If the gearbox is not in gear it should turn freely from the input end. If the gears are still engaged it would stall or you would feel like you are being pushed along. Stopping the car tilts everthing forwards, are Your engine and gearbox mountings tight/in good condition? If not that can cause judder.
When in neutral the drives into the box are from the input shaft, but no gears are selected or the Tbox output shaft still being turned by the road wheels via the prop, have you checked Tbox oil levels etc?
Re-reading your post i'm tempted to think that the gear lever linkage is the problem - hard to select and feels like its still in gear - maybe it is? I'm not a gearbox expert but that Ashcroft fella is. I think he posts on LR4x4, maybe he could diagnose it for you.
Stu.