I know this isn't exactly an answer, but my vectra has just done the same thing. Drivers door wont open, but the central locking works, the dead lock doesn't work, and reset the key fob in the ignition doesn't work. This only happened 2 days ago, and I've asked my brother who knows a lot more about cars than I do, and he reckons that it is just a relay! He says just a relay, but that relay is inside the door. I recently had to take the panel off the passenger door, with the door OPEN, and that was hard enough. The car is being booked in the gararge tomorrow.
Sam, April 2007