Recurring WoW Disconnect Problem - Help!

[ElMaskedNacho]

I apologize for posting a help thread on the forums however I've been running out of options, even though I've been talking with Blizzard support for awhile now. Here is the summary of the problem, which I sent to Blizzard:
"I would have to estimate that this issue has been occurring since October-November until this day. I boot up, World of Warcraft, then enter my account information and authenticator. I am connected to the server and sent to the character selection screen just as normal.

I select my character and press enter world. It is once the loading bar is complete however, that the disconnection occurs. I get into the game however all of the NPC's have the name "Unknown" and I cannot interact with anything. I am then greeted about 5-10 seconds later by the "you have been disconnected message."

The odd part of all of this is that my entire internet ceases to work for a period of time following this. This period of time is usually very long, as last night for example I attempted to connect at approximately 1AM and the internet did not come back until about 6:30AM. I have fully reinstalled the game twice. Both times I was able to log in and play the game perfectly fine with the first log in.

However, once I exit and log in to start a new play session, it is on this second attempt that these problems occur again. I believe however, that it is only this computer and that if I attempt to play WoW from a different computer it will not disrupt my internet for 5 hours, therefore I can localize the problem to this computer. Any help on this issue would be greatly appreciated as I have never had this problem before and I would like to return to playing the game after months of being unable to. I appreciate your time and thank-you for your help."

Here are my computer specs:
CPU: AMD Phenom II X4 945 Processor - 3.0 Ghz
Motherboard: GIGABYTE GA-770T-USB3 ATX AMD
RAM:OCZ AMD Black Edition 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)
Graphics Card:EVGA GeForce GTX 460 (Fermi) 768-P3-1360-TR
Power Supply:CORSAIR CMPSU-650TX 650W Compatible with Core i7 Power Supply
Operating System: Windows 7 Home Premium
Resolution: 1920x1080
WoW Settings: Occurs with any configuration.

Blizzard has told me to do the following things, which have not worked:

"Click Start, then select Run and type CMD in the Run box. A command prompt window should open on screen.
Type ipconfig /release in the command prompt.
Wait a few seconds for a reply that the IP address has been released.
Type ipconfig /renew in the command prompt.
Wait a few seconds for a reply that the IP address has been re-established.
Type ipconfig /flushdns in the command prompt.
Close the command prompt and attempt to make a connection."

Any help would be appreciated! Thank-you all for your time.

Edit: By creating a new account on my computer I am able to temporarily fix the problem by playing on that Windows account for a few days until the problem starts again.