Access to Internet via Remote LAN connection

I'm running a small ethernet LAN in my home using Win982ed and I'm using internet connection sharing in order to give all the computers access to the cable modem and the internet. On the same computer that hosts the cable modem, I have a regular (USR) telephone modem. It mostly behaves as an answering machine, but it also hands off data calls to the Dial-up Server software so I can get at my files etc. What I want to be able to do is to be able to use my laptop when I'm on the road to dial in to my home computer and access the cable modem's internet connection. I think this involves configuring TCP/IP and subnetmasks, but quite frankly I find it all a bit confusing. Can you take me through how to do this?