Ok, thanks... I've booked it in for a service on Friday morning. Thing is I've got to drive about 10 miles to the garage... I've driven it with the light on before, so hopefully it survives.
Warning lights on the dash panel are usually orange and red. If the orange light changes to red, thats the sign of a serious problem and should be looked at with urgency. The orange engine lights can be a mutlitude of things from low power out-put from the battery, wrong air-fuel mixture, slight misfire and so on. A diagnostic resetter usually switches off the light, and thats the end of the problem. There are mobile operators who normally charge approx €60-70 for same, and if it cant be turned off, they can tell you what problem is.