Re: wireless router trouble.
First, I would not recommend using the software included with the router. Plug the Router into the DSL Modem and her laptop into the Router directly. Make sure the modem is plugged into the broadband port on the router. It is usually set aside from the other ports. There are usually 4-5 ports on the back of wireless routers. Then type in the following address in an IE window: 192.168.1.1. This will bring up a web interface for the router. From here you can configure its settings. The address is pretty standard for any hardware and if she is currently connected to the DSL modem, then she has ethernet connectivity.
Start here and then reply back with further questions and in your reply include all hardware being used and OS version.