wireless connection to home network

I can't figure out what I did to screw up this laptop's wireless -- it used to work, until I tried to network the laptop with my desktop PC. Now the laptop does still connect to my home network via Ethernet just fine, and it also connects wirelessly to every other network (which is not very many) that I've taken it to visit, but when I try to connect to my home wireless network, it just reports Status: "Acquiring network address" forever and never connects.

The home network uses an Actiontec DSL Gateway, GT704-WG. The laptop is WinXP pro; the desktop is WinXP home. I took screenshots of dialog boxes for some of the laptop's settings, they're here: in a Picasa album -- please let me know if there are other screenshots that would help.

Suggestions? I don't really understand how most of this works -- I've managed to get what does work going by poking around and trying stuff, and I'm sure that's how I broke what doesn't work. Thanks for looking!