I don't know why I haven't seen more complaints of this, but for both me and another colleague in my office, when Chrome is running (this is in XP) the system freezes for several seconds at totally random times, even when Chrome is just sitting in the background. Total deal breaker.
What's your HD doing during these freezes?
It's like the old days in Photoshop, when you need to give it its own dedicated scratch disk...