Windows 7: Unidentified Network?

If that is the case, why don't any of my other computers have this issue? Is it possible to configure the modem/router to behave like a "standard modem"?

I gave you all the info you need to make your network reliable.

You might try asking your ISP for a standard modem instead of a combo unit.

I contacted my ISP and they stepped me through turning my modem/router into just a basic modem. Having done that, I'm in the same position as I was before, where just the 1 computer does not connect.

Disabling DHCP on the modem/router may or may not fix this problem depending on many factors.

The problem I noticed in the last ipconfig was that you have nothing coming from your regular router so it probably needs to be reset or the correct settings haven't been typed in.

You will need to type in two DNS servers into the settings on your regular router and also enable DHCP on your router.

After doing that try posting the ipconfig/all again so I can see if the secondary default gateway is gone and that you are obtaining an IP from your regular router.