scottish scooby

Hi i have a 2003 2.5 petrol subaru legacy that has been sitting for a year and a half now and i need to get it running for its MOT i have just charged the battery and changed the battery in the key fob as both were dead but the central locking isn't working and the car wont start i think it is because the key wont shut off the immobilizer because all other electrics are working and when i turn the key the dash lights up just as it should but wont start if anyone could help me with this it would be much appreciated thanks