http://www.urbandictionary.com/define.php?term=talk_to_the_hand and wikipedia give more setails on the use of this 'rude' slang (with a hand gesture). Its use has been declining since 1900s. I personally would not consider using it in any situation. A polite "sorry, I don't have time for this." or stronger "I won't hear/'listen' to this.", or rudely "that's bull..." would produce the same effect. ;-)