WRT54gs router problem

Hello,

I recently did a reset of the WRT54GS router since I have long ago lost my CD with software on it. I am using two laptops at home, one wirelessly downstairs and one hardwired upstairs, next to the modem and router. After the reset, I was finally, after 10 tries, able to access the set-up page through 192.168.1.1 address. I entered everything as was mentioned on various forums. I saved all the changes. However, after all the steps taken, I can't still use the laptop downstairs wirelessly, since it does recognize the router with excellent signal but is unable to connect to the internet. Also, since the reset and the configuration changes, I cannot use the laptop upstairs that is hardwired to the router, only when I connect it to the modem. Please, write me back exactly what am I suppose to do and what steps to take next/. Thank you