I have a home which was built in the 20's or 30's. Electrician updated service to 100 amp from 60 and inspected previous rewiring job, installed GFI's, etc. Discovered new wiring to numerous outlets-bath, frig, computer and office area, bedroom, from an ungrounded junction box on old wiring which was (illegally and stupidly) buried in construction by a previous owner. The old wire wire runs from the service panel to the outside of the home, back inside the home, and then to the junction box in an uncertain location. Tried to locate junction box from outside as way to create least damage to repair and found house was originally brick. Only way now to actually locate junction box to ground and replace the one piece of old wire left in use in the house is to start tearing ceilings out. I am getting confused on what is a safety issue to person or property, shock or fire or surge, and all the options I am being told. Electrician has not dealt with old houses much (he tells me now!?) and that only right way to fix problem is to tear out ceiling(s?)but he could install GFI outlets and run new wire exclusively to frig from service panel-my call. He tried GFI breakers but they just tripped. Other people who are knowledgeable but not electricians are telling me to have new wiring run from service panel to frig, maybe washing machine, maybe bathroom, new grounded outlet for computer surge protector, and put rest of outlets (currently and incorrectly on 3 prong outlets)on GFI's or go back to the 2 prong so they are clearly not grounded, but are either of those options safe to person/property? I can't afford a bunch of reconstruction but also do not want to put $$$ ahead of my family's safety. Help me please!!!