First thing I'd suggest is checking 2wire's site for a firmware update for the gateway. 50/50 chance at tha, though, as the ISPs themselves often are in control of their gateway firmwares.
Laptop is running Win7, I'm guessing?
Things I'd try doing on it:
1- check HP (or the wireless card's vendor) for a newer driver for its wireless card. Driver recently updated? Try rolling it back to the earlier version.
2- try it wired. If it still borks your gateway, continue on to the next steps (issue is with Windows, not with network adapters or drivers.)
Still borked when wired?
1- disable IPv6, and check function. Note, though, that if you're running a Homegroup, this can only be a troubleshooting step. Homegroup requires IPv6 (you can re-enable it later.)
2- reset the TCP/IP stack on the laptop. To do this: open an Elevated (Administrator) command prompt, and run the following command:
netsh int ip reset C:\resetlog.txt
and reboot when it's done processing that.