I have two computers one windows 7 that I use to get on the internet, emails etc.. The second computer is a Windows XP that I plan to use only off-line for preparing, storing, and printing lessons, (Microsoft 2003), backup for docs., doing Artwork etc. QUESTION: Do I need a router for either of these two machines?
A router is a device that will plug into your modem and allow you have WiFi in your home. If you want a wireless signal available for your Windows 7 PC or any other devices like a tablet, you will need a router. Or you could choose to have a wired connection and connect your Windows 7 PC to the modem.
Since your XP device is not going online, it would not require a router. Unless you decided to link it to a shared server in your home.
To learn more about routers and severs, click here.