Battery removal?

Might sound really stupid, but on a D2 if I disconnect the battery whats the procedure? I`ve heard the alarm might go off, the airbags might go off etc.
Will reconnecting the battery re-boot the system? Thought it may cure the G/box problem I`ve posted about previously

If the car is unlocked with the fob(it means the alarm is also disarmed) then u just remove the negative lead and no probs. When u reconnect the battery wait a bit(1-2 minutes) untill the IDM and the BCU reboot themselves, ..... u have to reset the clock aswell and reenter the radio code(if u still have one). That's all

What if i dont have stereo code? Can i put a new one in before disconnecing the battery?

Nope(at least i donno that)......but if u dont have one u dont need one