Problem with APIPA and workgroups.

I am having a heck of a time and am struggling with how to fix it.
I have the following equipment
Linksys WRT54G wireless router
PC #1 hardwired to router running Win XP Pro 64
PC #2 just reactivated with Win XP Professional just installed over Win XP Home and with a Lynksys WMP54G PCI Adapter.

I have no problem with PC #1. It accesses the internet and the TCP/IP was set by default to Obtain an IP address automatically.

I currently am using Charter Internet with a modem connected to the router FYI.

The router is set to WEP security.

PC#2 is connecting properly to the router but failing to connect to the internet. The PCI Adapter somehow went to APIPA the private IP rather than defaulting to the Obtain an IP address automatically.

I also have tried to set up an office workgroup but can't seem to get that going either.

I have successfully linked my ROKU player to my router so I know it is working but this has me tearing my hair out.

I have uninstalled/ installed the wireless card but that hasn't helped. I have read a lot of info about changing my registry but that is kinda scary to me so I am hoping there is an easy fix. Any ideas?