You have a few options.

Do you know what the zone #’s are for these doors? If so you can bypass them, but you’d have to bypass them everytime you arm the system. Press B/A on your keypad, then the zone #. Repeat with the next zone. Do this before arming the system.

Yes, you can remove the doors from the system. You need to null them out and/or remove them from the partition. To do this you’d have to call the company that you were last monitored by. The only thing is companies don’t normally allow the owners to go into programming of the panel. Plus they may need to supply you with the installers code which again, most companies don’t do because the # belongs to them and another monitoring company could access your panel using that #. Your best bet would be to have a technician from your old Monitoring company come and just null the zones out. They’ll charge you but they’ll know the zones, the steps and the installers code. You may want to ask them to bring a battery with them because chances are if you’ve had your system powered down the battery is dead.