Disposable

Over the past few days i used the entirety of my download limit, and i could not see why until i realised my internet was downloading constantly. I began ending processes that i knew were not important until i was left only with a few needed process and my 12 svchost.exe processes. Ive now norrowed it down to the one that uses the second largest memory, and everytime i end it my network usage with hit 0. Now.. i can keep ending it like this, but its annoying and i was wondering if there is any way i can stop it doing this. Im too afraid to delete it incase it causes problems being associated with sytems processes.

Thanks for any help