Your not hacking are you?
The IP address the remote computer will see would be the linux box unless its masq from a firewall/router.
I will admit im usure if the remote computer could see the ip of the windows box but definitly the windows box. But your actions would probably be logged on the linux box.
Just a quick tip for you. Instead of telnet use ssh.
This will provide you with extra security. IE: Passwords will not be sent in clear text like telnet.