It's definitely what I would look in to, some alarm systems are more elaborate than others and it depends on how they have been installed. Had an alarm on my Golf that I literally just unplugged and the car still ran fine. Other alarms and immobilsers end up being soldered in pretty well...
Just take it steady and try to unplug rather than cut things at first and see if you can get the immobilser to disengange. You can worry about sorting it out properly later as long as you can start it now