Hi!

I am new in the linux world. I was using windows as long as i can remember, but for the past month i only had problems with it. So i decided give linux (Ubuntu) a try through wubi (since i dont have enough knowledge about partitions). I understand almost everything. But i have question about viruses. I know they cant be used in wubi, but if i download any can they execute themselves in windows without me knowing it? I mean if i download virus but i never execute the program that contains it in windows and never even boot windows can they still be threat to it?