first turn off all computers
turn off the modem and the router by unplugging them.
plug in the router, let it sit for like 10 seconds. then plug in the modem. let it go into the cable modem running through its set up.
after the the modem is done loading, turn on one machine
go to start> run> type in cmd> then ipconfig.
do you get a 192.168.1.* ip address for that machine?
do you have a link light on the network card? and where it is plugged in on the router?
do you have any software firewalls running.
can you access the web configuration page in the router?
http://192.168.1.1
password admin (hopefully you have changed this by now)
if you can, click status and see if you are getting an ip address from your isp
do you have the latest firmware installed?
http://www.linksys.com/download/firmware.asp?fwid=160
(read the readme file, its tells you very simple how to install it.)
also does your ISP use PPPoe?
one more thing, i noticed you are using a wireless router.
please take time to read over this thread
http://www.techimo.com/forum/showthr...light=wireless