Need help in debugging Email wireshark capture

I am completely new to wireshark.
I have been given an assignment to analyse email capture with wireshark.
Can anyone please help me how to proceed further and what I should look for in a wireshark capture?

This may be a little late for your assignment, but the explanation I posted on this thread covers some basic ports and such for email. Hopefully this will help somebody out when they search for it.