Problem with IP address & router

I have a Dell Dimension 4100 PC with Windows ME.  Also has a D-Link PCI Adapter card installed.

 

My daughter has a HP Compaq Presario laptop with Windows XP that we are trying to establish a wireless connection (actually, we have that  - but cannot access the internet on our PC)

 

We are using a Dlink DI-524 Wireless G Router and have Comcast for high speed cable with a motorola surfboard modem.

 

I can get onto the internet on the wireless, but not on the PC.  I talked to Comcast and they said all was well on their end  and to talk to D link.,  D link came up with the problem that the IP address isn't recognized on the PC and told me to talk to the computer company.  Has anyone had this problem.  The router is connected to the PC and also to the cable modem.

 

Sorry about the first incomplete post - I'm not used to the laptop & must have hit post.