Wireless Connected - No Internet Access

I've got a friends computer I'm working on and I'm a bit stumped. Running Windows XP SP3. Windows update running automatically, AVG and Windows Firewall enabled. I also scanned with Malware Bytes, nothing was detected. Here is the scenario:

Both the Wireless and Wired connections recognize that they're connected with good signal strength on the wireless. It's not specific to the network, he's tried from his home and business and now I'm trying from my house - all with the same results.

I've uninstalled and re-installed the wireless adapter. I've refreshed DNS cache and gone through the whole ipconfig /renew process.

I can ping outside sites -- pinging Yahoo.com for example resolves to the same IP on his machine as it does on mine.

All that said - when I open a browser (IE and FF both do this) I can't connect to anything. I'm not sure if it's relevant or not, but IE always opens two tabs, both attempting to reach his homepage (google.com).

Any thoughts? What am I missing?