You can, I use bukkit for my server so i'm unsure about the offical server tool but if you just free the port you wan't to run the server on (You do this on your router, if your unsure how to use your router, refer to your router's manual if you have it) then you launch it (obviously) (change the config of the server so it''s using the port you opened if you opened something other then 25565 before you launch)
Everything above this point is wrong. You don't need to forward any ports if you are connecting via the local network. In fact, it's safer to NOT forward a port so that the server can only be accessed from within the LAN.
then get him to type your computers local IP and that's it!
If you don't know your local IP open up CMD (Type CMD in the StartMenu search) and type IPconfig, you wan't the IPv4 Adress.
Hope I helped :D
The rest you got right though - just connect to the servers local IP and have fun.