If you run
netstat -b, you can see the applications that have the specific ports listening. You can't (to the best of my knowledge) close ports on demand, only terminate the processes that are accepting the connections.
Also, I think you're confusing MAC addresses with IPv6 addresses.
fe80::b970:58f1:a42a:a333 is not a MAC address; it's an IPv6 address. Problem solved; you've got the IP.
(Information below this line is irrelevant if you don't have a MAC address)
Furthermore, even if you knew the MAC address, I don't know if there is a RARP (Reverse Address Resolution Protocol) for Windows. I know there used to be
rarpd for Linux, but RARP support was removed version 2.3 of the kernel. You could always fire up WireShark or something similar if you're on a wireless connection or connected to a hub (not a switch) and check the destination addresses of the frames.