As everyone else here said, Wireless is not for gaming.
I looked up that USB wireless adapter and found that even the v4(Which sounds like the version number, so I believe its version 4) does not like to work with Vista 64Bit. I also believe it only has XP drivers as well.
If you want to game with this computer it would be best to hard wire it with Ethernet or get a pretty expensive PCI one. The problem with Wireless networking is that the ping is bad. If it takes over 500ms to communicate with the sever its not good for gaming. I get(Verizon Fios here) a ping of 10ms on my gaming PC which is wired with Ethernet on Speedtest.net. My computer in my basement which has a wireless connection gets 200ms-1000ms.
Latency makes a big difference in gaming as well as upload speeds. Wireless also has bad upload speeds which is needed for gaming more than download speeds.
What computer are you using now? Is it wired with Ethernet or is it wireless? If its wireless try testing it to the closest location on speedtest.net and post the speeds you get including the latency.
Here's three tests on my Gaming computer(Ethernet wired):
Don't ask how I got this speed one day, its just on my record for my IP address:
This is my computer in my basement using a wireless PCI card:
This is the same computer using a D-Link WUA-2340 USB wireless adapter:
Push pins are weird in my mind. My dad's computer uses a thermaltake HSF that using push pins and I think I broke one. Do you have to turn them to lock them?