No can do, because there are simply too many possible reasons for lag, many of which involve systems beyond your ability to control.
I can say, however, that wireless for online gaming is about the worst possible thing you can do.
Hello,
So, I was playing Modern Warfare 2 on my Xbox 360, and suddenly, I am lagging like crazy. I am using the grey Wireless Adapter and have a Motorola SBV5222 Modem and a Netgear WGR614v9 router. Please help!

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