When an airliner gets lost, and receives warning shots from interceptors, how should the pilots react in order to save the aircraft?
First off there are established interception procedures under international law so they are not going to shoot at you upon overtaking you.  Typically an element of fighters form up on the jet with the leader maneuvering into formation on the jets 9 O’Clock and the Wingman stays on the jet’s six.  They will do so in a manner which allows the intercepted aircraft to see the lead fighter.  There are a series of established visual signals ie rocking wings for compliance, deploying flaps and landing gear, etc.  if the intercepted aircraft cannot communicate with the fighters or ATC, they will squak 7600 and ATC can relay this to the fighters.  Other means can be employed to get the attention of the intercepted aircraft such as the lead fighter cutting in front of the intercepted aircraft while in afterburner, etc.

If it does come down to where the authorities determine you are a threat and use of deadly force becomes authorized, the fighters are going to let you know in a clear and unmistakable way.  Unless you are armed and intend to engage, you better comply!