As a quick first look, I would check and clean any crud off the Crank Position Sensor and the Idle Air Control Valve (IAC). These may not be your problem but are quick and easy to do and you never know... It shouldn't be necessary to take apart the IAC but if you do, be warned that bits can fly several metres away! Also, don't be tempted to operate the IAC while not fitted to the car as a similar thing can happen!
