Problem with Network - Unable to ping Gateway and beyond, unable to access files

I'm living in a house using a network (both wireless and wired) to connect to the internet. Everyone but myself is able to view files shared on the Network. In addition, I am unable to ping any host beyond my computer (Gateway and beyond), using either the command prompt, or pinging programs (I've already tried a variety. Any suggestions for troubleshooting, or settings I should check?

I'm using a Dell Inspiron 9300 XP home
512 MB Ram
1.7 Mhz centrino
Broadcom 10/100 Integrated controller

If more information is need (obviously), tell me what you need to know.

 

Make sure your IP addres is on the same subnet as the other PC's and the default gateway should be your router. Also check your Domain it should match everyone elses to be able to file share. At tthe command prompt type

ipconfig /all

Do this on you PC and one that is working and post it here.

Rick