Sorry for the late reply.
Good question. I am not completely sure about what you mean by bringing boredom. Do you mean someone that doesn't have much to say, or someone that asks the same questions repetitively? If it's the former, then I wouldn't do anything - some people are big talkers and others are not. It it's the latter, then the best approach I find is to have a sticky FAQ thread which you can politely point people towards.
Angry people are different. If their anger means that they are rude to other members, I would discipline them immediately. If their anger is general, then usually a polite PM does the trick. There will always be people that just want to cause trouble and in the end they spark their own demise.
Please let me know if I've misinterpreted your question.