I had the same problem in my place, I have two towers hooked up to the router and one laptop and all weekend it kept cutting out, i’d get disconnected from msn, or kicked from servers in game.
I couldn’t figure it out so I checked all the phone lines in the house and as it turns out, one of the beds couldn’t be pushed right up against the wall with the filter plugged in to the phone line so they removed it.
so every time the phone rang or someting picked up to make a call my connection would drop then come back and drop and so an and yeah put the filter back in and it hasn’t happened since.
I used to live on 11th close to mc donalds and we’d have really horrible service all the time paying for the full dsl and getting 14kb/s download 0.01kb/s upload, i’d call and complain and city west told me I lived too far away from their server to get a good connection.
now I live further away closer to the seaplane base and my connection is a lot faster then it was when I lived closer to city west. one thing you can try is check for those damn filters, make sure you have one in every phone jack you’re using.
also check to make sure you have your wireless set up with a password, and theres only people in your house using it. when I bought a new wireless router last year I didn’t bother setting it up correctly and when I checked it a week or two later I had six other people using my connection.
nothing worse then people moochin your net causing your slower the normal speeds and random disconnects.