"Local Only" on Vista Computers

Okay all of you brilliant minds out there...I need your help

Out of the blue both of the Vista Home computers in my household are unable to make an internet connection.

All previously were able to connect. Any XP or Windows 7 computers can connect.

I want to make it clear that they DO connect to my wireless network, but not to the internet.

I have done:

• ipconfig /release
• ipconfig /renew
• ipconfig /flushdns
• deleted the network device manager and restarted
• deleted the wireless network and re-installed
• unchecked TCP/IPv6 (rechecked it when I could not connect w/ my network)

Ipconfig /all reveals that the Default Gateway is not present (the field is blank). It is there on the XP and the W7 computer.

Correct me if I am wrong, but I should assume that my wireless router is working? Right?

I tried to download this update from Microsoft, but the validation for "Genuine Microsoft Windows" checks the version for my XP desktop that does connect to the internet, but when I try to install the download on the Vista machine it says the "update does not apply to my system".

I also went through most of this checklist I found while searching for a solution.

I tried this also (a possible internet solution):

Problem: The problem come from the new tcp/ip stack integrated in
Vista.. I couldn't get any IP from a DHCP server. I could see the
Access Point and connect my laptop on it but never get any IP from my
DHCP server.

How to solve: You have to modify a key in the registry to make your
Vista able to get an IP from your DHCP server.

1. Click the Start button.
2. Select All Programs > Accessories.
3. Right click Command Prompt and click Run as administrator.
4. Type regedit.exe and press enter.
5. Go to the following location: HKEY_LOCAL_MACHINE\SYSTEM
\CurrentControlSet\Services\Tcpip\Parameters
6. Right click this entry and select New Dword.
7. Rename the new entry ArpRetryCount (leave it set to 0 by
default).
8. Restart the computer.

No luck so far...Whiskey Tango Foxtrot!!!