But the rifles are far more dangerous in a "neighborhood" or suburban setting than a handgun or a shotgun. But other than than that +1 on the shotgun and 00BLooks like her tactics were sound. Hole up and wait for the cavalry and own the room you're in. The only thing she could have done differently IMO is either an AR-15 or AK with soft-point ammo or a 12 gauge with 00B. I have a feeling she was using a handgun.
Rifles and shotguns are far more effective for something like this.