The dogs you said were "protective" of your property - do you mean they barked when someone came to the door? Did they try biting everyone who walked in the door? :) Did they know the difference between friend and foe? Barking doesn't mean they will protect anything at all - many dogs will bark (sometimes because they are afraid, or because they want *you* to do something...) And do you really want a dog who is dumb enough and fearful enough to feel that everyone who merely walks in the door is a threat?
Anyway, what I mean is, you want your dog to be happy and confident when someone is entering the house when you are there, or if he knows the person - he's a smart and confident dog!
As to what a two year old, confident, Rottweiler will do if there is a real threat - well, I don't know, I suspect many will turn tail and run if there is a real threat to their safety. Big and scary-looking is enough of a deterrent for most burglars - any experienced burglar can get past most dogs anyhow, even mean ones, unless perhaps the dog has been protection trained.
I don't know what any of my dogs would do if a stranger entered the house when there was nobody home. One I know would turn tail and run if there was any threat. The "boys" have not been tested, but actually I think they would probably go after most intruders, (I could be way wrong though.) My
old dog actually did scare off a burglar when she was younger, chased him out of the house - I know for a fact she would attack someone unauthorised. All my dogs greet everyone who comes to the door very happily though. You should be glad yours does.
I'm not sure how it works in Russia - most people in the US would face really large vet bills and be liable to get sued if their uncontrolled dog was running about attacking other dogs - not to mention the dog may be taken by authorities and killed. This is generally not regarded as a good thing - you have a young dog who is being a bully, attacking other dogs who are not being a threat to him, and ignoring you....he sounds like a dog who needs some training and manners. He sure doesn't sound like a dog who should be off leash around other dogs. Both of my males have a tendency to be stupid and dog - agressive, I have spent TONS of time and energy training them not to be. If this is a concern, do a search on dog agression on these forums.
Raw meat will NOT make a dog vicious. This is a complete fallacy, and a very common myth.
Mine eat raw meat every day; none are "mean."
Isolating your dog will NOT make him protective. It will make him sad and frustrated, that's all.