I have 51 processes running without MW2 open.

yea that doesn't seem right even for windows vista/7, if you could take a screenshot of all running processes from all users i could help you find out which ones to disable also from
start click run or on vista the search bar type msconfig and hit enter

for the startup tab un check anything that isn't required by either a video driver, sound driver or wireless card driver if you use the gui instead of regular windows wireless settings

in the services tab after you've done all that check hide all microsoft services and again disable anything that's not required for your videocard or sound card

this requires a system restart

...I am using windows xp

definately not good then... that's likely to be the problem

those steps work with xp btw just did them on my pc as i typed the steps to make sure i didn't get anything wrong

well with windows 7 that's closer to normal but still no, unless you have 2 users signed in at the same time and you just quick switch between the two. even still though you might have a similar problem that may not be virus caused

i was wondering when someone would do that