Having Lag Spikes in Online games (Latency)

Hi I was wondering if this was the right place to ask this, since I've been having problems with latency with my internet in online games, namely on the STEAM program. I'll be playing in a game and I'll have decent latency of about 40-50 but then either a few seconds or minutes later it will spike to 1000 - 2000 latency for like 2 seconds than go back down.. and this is constant, it will stop sometimes but it will always start up again. I'm not sure if this is a virus problem or what, I've already scanned my computer and everything and it just affects my online gaming, it just gets frustrating playing an FPS game and then all of a sudden lagging for a split second and then being killed. A little help or insight on this problem would be nice, thank you.

I am also using Windows XP 32-bit

Edited by DeadEye211, 05 July 2010 - 11:29 AM.

Do you have any background programs which might be hogging your resources? Do you use any internet related programs such as P2P applications? Try disabling all startup programs and non-essential services, reboot, try your game and see if it helps.