I agree, but it seams like the primary translation has been changed from "chatting to" to "talking to", which my comment was directed at. Besides, there do exist situations where it would be natural to say "speak with" instead of "speak to". It depends on whether you are the only one speaking, or it is more of a two way communication. "Dad is speaking with my teacher" seems to be an example where this could work.
Yes, kusema would be best translated as to say, and kuongea would be translated as to speak or to talk. At least this is what my Kenyan friends told me. It might be different in Tanzania. I'm not so familiar with the word kuzungumza, but I guess it's more in the sense of conversing or discussing.