I can't tolerate when DS throws things at me. He doesn't do it very often and after I've had a reaction (yelling!) I go and figure out with him what's made him frustrated. After all, he's 18 months old and can't TELL me what caused him to throw something at me!
As for thank you, I would prefer he mean it before he says it like a mantra. I would much prefer to hear a thank you from a child who was actually aware that they owed their newfound happiness (for that cookie, glass of water, whatever) to my actions. I DO like to hear 'please', and if it's not forthcoming, I prompt gently. If it was asked without please and they seem confused about my insistence on the word (and it's a young child), hell, I just give it to them, it's an advanced kind of concept anyway!
Violence of any kind will not be tolerated and will be dealt with sensitively and lovingly. I've studied violence in societies before and it's a cycle that needs interrupting with love