Vista - WoW problems

Ever since I bought my new computer with vista vista ive been having these "lag spikes" every minute or so that last about 2-7 seconds, where everything around me character just runs in place. It seems as if the internet is being interrupted every minute for some reason, but I cant figure out why. The problem is either OS or computer related, but I cant figure out how to fix it.

Do you still have your old computer? If so, does it happen on the old machine?

Have you tried disabling the built-in Vista firewall?

How about running the task manager and watching it to see if anything is grabbing a lot of CPU time every few minutes...

My old computer didnt have these problems, it still happens when the firewall is turned off, and even when i disable most of the background programs it still happens.

Is the Blizzard Updater running? They are close to releasing the 3.1 patch and whenever you run WoW, it downloads more of the 750mb pre-patch files.

Other than that, I don't know. I don't have any of those problems. In fact, when I moved to my new machine with XP64, WoW runs better than ever (I get a pretty consistent 100 fps, even in raids).

its not the game itself, since it worked fine on my old computer in the exact same spot this one is in now. my friend fixed the problem a while ago by downloading some kind of program that stopped the interruptions, but I dont know exactly what it was.