Help with connecting to wi-fi?

I need help connecting my wireless wifi with my desktop(tower) computer. How do you do this?

• my internet is obviously working as we speak, but I haven't setup my wifi connection. My computer is a bit older. Its a windows xp, if that helps any & everytime I go to my "control panel" & click the "wireless network setup"- it really doesn't work at all. All the lights are green except the wireless on my at&t router. Its just blank. The account is in my name, but in the same household are ground phones that are in a relatives name. Ironically the same day I connect to the internet is the same day she can't use her phone. What is wrong here? Please help :( She is starting to stress me out since she can't use her phone & I'm assuming since I didn't connect my wifi. Serious answers ONLY. I can include more details if you know how to fix this problem. thank you :)

• Answer:

  So it seems you have DSL that connects to the telephone line. To use DSL you must have a filter on every telephone plug in the house, even ones without a phone just now. Without these the phone and the internet confict with each other. Now about the wifi. My guess is you have just a DSL modem. This does not have the ability to give you wifi. You need to buy a wifi or wireless modem. The instructions will give you the step by step instructions. Most come with a CD that helps you connect. Now, in the rare case that you may have a DSL modem that ALSO has a wifi router attached, get out the manual. Generally you must have the SSID (router name) and the security key. Sometimes this is on a label on the router/modem. Then Click the wifi icon at lower right, click View all Networks, then find Setup Wireless Network. Follow that to give the computer the SSID and security key. That should do it.