I am talking to Jane. I speak with her every day. She said that she is graduating next week. She will tell me what time to be there.
John is telling me a story. He spoke of a time that has long passed.
The CEO gave a speech yesterday. He spoke about how the economy would impact the company.
Let me know if you would like to talk about this. I can tell you the meaning of each.
Usually talking and speaking imply two way conversation but not always while telling and saying imply 0ne way.