unlikely to be a clutch problem (if you put it into gear and slowly release clutch pedal with your foot on the brake the engine should stall if not worn) and it shouldnt judder. Could be worn indent pins on selector or thrust washers ie worn gearbox or bad engine mounting allowing engine to move. causing gearshift cable to pull out of gear (very unlikely). mainly a worn out gearbox problem.
john, January 2007
