I'm on Windows too, which makes things a bit difficult for developers (surprise!) but I've written a newbie guide which I hope will help you set things up: http://wiki.dwscoalition.org/notes/Newbie_Guide_for_Windows_People_Working_on_Minor_Bugs. If you've never done anything like this before I know it can seem overwhelming at first so feel free to ask me questions (here or via PM).