your talking about ping which is the time in takes in miliseconds to get to the server and then back to you, this can be affected by many things usually it is because you or someone else is using the connection which can obviously slow your rate and affect yourgameplay,I'm not sure what you need for mw2 and such it just says broadband connection was it ok before? or is it just recently that its not working ok? 1Mb sounds like enough but i, unfortunatly, havent had chance to play it yet.
I'm from the uk and i'm with a company called plusnet.
btw you are correct dividing by 8 gives you a good estimate of you d/l speed your download rate should be around 125KBs.
I'm gonna continue play the first modern warfare, on the guilli suit level