[My whole home network] No internet, just get "Limited connectivity" message!

First time poster with a doozy of a problem... no internet across my entire home PC network. Can't get work done, check email, and kids are screaming bloody murder to check on their WebKinz... any help appreciated at this point!

It started a couple nights ago. At first I thought it was my cable modem or service (Charter). But no... their tech support says their service is online, and they can see my cable modem fine on their end. And sure enough, when I plug my wife's work laptop directly to the modem, the internet works fine. But doing the same with any of the home PCs (directly plugged into the cable modem via cat5) does NOT work.

The details: All five PCs on the network are showing a "Limited or no connectivity" message under Network Connections. All PCs except for one roving laptop are connected via CAT5. Since this problem started, I have disconnected the network hardware (Linksys router, Buffalo Wireless airstation) and now I'm just trying to get any of my PC's to talk directly to the cable modem. When I first plug in the Cat5 cable to the PC (other end is connected to the cable modem), it says "acquiring network address" for a minute or two, and then comes back with the "Limited or no connectivity" message.

Ipconfig seem to show that these PC's can't find an IP address. Here's what IPCONFIG was showing on one of the machines while connected directly to the cable modem:

Connection-specific DNS Suffix:
Autoconfiguration IP Address : 169.254.166.116
Subnet Mask : 255.255.0.0
Default Gateway :

Also - I've tried to "Repair" function for the network connection. No dice.

Is this a virus? Rootkit? Or other malware? I'm fairly versed in this stuff (for an amateur that is), and I'm stumped. I typically run ZoneAlarm and AVG or Avast on these PCs, but occasionally visitors connect to my wireless with who-knows-what protection. So far, on one of the PCs (the roving laptop, now hooked directly to the cable modem) I've turned off all virus software and firewall - no workie. Tried setting up a manual IP connection (based on the IPCONFIG info from the wife's working laptop) - still no workie.

I've run all the scans suggested here, following the MajorGeeks sticky to the letter - logs are attached. (Fyi, I wasn't able to accomplish the update step for SUPERantispyware because the PC won't talk to the net, but I did run it as described.)

Help!

Best,
Aj

 

And here are the MG zipped logs...