how can i fix my vectra 2.0 di?

my vectra teperature gauge got up to 90 c.car then lost power while on motorway maaged to restart it to get home but now it won,t start until bump starte for around half a mile.when it does finally start it sounds like it will stall asthough not all cylinders are working.and oil lighht then stays on until revved. i get power whn stationary but not much when trying to move,.please help?