I use Vista and have a wireless connection. Thrilling. But what wasn't so thrilling was the lag I was getting when I would play any game online. Every 20-60 seconds, I would get like a 1-3 second hitch, causing my connection to basically stop working. In TF2, for example, my dude would stop running and that red text would come up in the top right saying there was something wrong with my internets. I just thought that it had something to do my hardware(router, adapter etc) BUT what is really wrong is something with Vista itself! Apparently Vista(and apparently XP too but I wouldn't know) automatically searches for available wireless access points every minute or so. This causes the current connection to freeze, thereby causing many holes in my wall. One day I was just so tired of it and dove into the internet to see what I could find. I found this lovely program called "Vista Anti-Lag". Apart from being aptly named, it does the job oh so well. Just install this gem and press the little "activate VAL" button. You can then game in blissful serenity. I hope I can save at least one person's trouble(and wall) with this post!

Edit: Here's a link http://www.codecase.de/en/software/downloads/vista-anti-lag