You should look into U.S.-based VPN services (cheesy list). You may need to upgrade / replace your router to one that can tunnel connections through to the VPN server. If you want to be clever, you might do this only for the TiVo (or whatever your ultimately streaming box might be), letting everything else run without the extra level of indirection.

In order to keep things as simple as possible, you might want to look at purchasing a dedicated TV for your bother-in-law, e.g., one of the newer ones that has built-in support for Netflix (assuming that's how you want to go). This lets you have a single remote control to do everything and that much less to troubleshoot.