LOST

To start, here are my system specs:
40GB Hard-drive
1.99GHz AMD Athlon Processor
1GB DDR RAM
256MB GDDR3 ATI Radeon X700 Pro (PCI Express)

Secondly, the equipment and ISP:
The router - http://www.netgear.com/products/details/MR814.php
How I'm connected to that router - Through a "802.11 Wireless LAN USB Adapter." It looks like a USB flashdrive with a long USB cable.
Our ISP - http://www.timewarnercable.com/piedmonttriad/ [Road Runner (Cable)]

The Problem:
When I play CS:S or DoD:S I cannot pass the "Parsing game info..." section of loading a server. When creating a server, it locks up at the Establishing connection to server" phase. Also, while I can connect to the Master Game Server to get the server list, it seems 'limited' as I only get an average of five servers per refresh. Now, once in a blue moon, I can actually get a decent sized list, join a server and play. Once connected I can seem to stay connected, but changing servers puts me back in my original situation.

What I've done to see if I could remedy this:
1. Disabled Norton
2. Checked to make sure Windows Firewall is off (About 100 times).
3. Called Road Runner (Twice) making sure that port-blocking or a firewall wasn't the problem.
4. Moved the computer into the same room (Three feet from the router).
5. Used my brother's USB adapter.
6. Contacted Steam, involving a conversation several emails long, and doing everything they asked. They can't seem to find it and they've had me running a system diagnostics test to see what was active on my computer.
7. Physically cleaned the PC.
8. Did a 'System Restore' via the built-in restore feature.
9. Connected directly to the modem via an Ethernet cable (This solved it, but IS NOT a permanent option).

[All these have been done in combinations and nothing but the last had any effect.]

Additional Information:
I had been playing World of WarCraft and am now playing Warhammer 40,000: Dawn of War. Both run/ran without issue.

So, if anyone here can help, please take the time to do so.