Think my system is at risk? I can give you my IP address and you're welcome to try...
As long as your hardware and the software you run is compatible with Win7, and as long as you take security measures (such as avoiding clicking on stuff you shouldn't be clicking on), I don't see why you can't get by..., at least for as long as your stuff boots. I mean, there are folks who still run legacy 32 bit OS/2 and Win 3x/DOS programs, on the latest and greatest AcraOS... gotta keep those Pentium Pros going.
However, if security and possibly a bit of privacy was my primary goal, and if connectivity was important, I'd be rethinking my priorities. Just to be on the safe side. Looking at some of the security centric Linux distros, or possibly something in the BSD family. Again, it depends upon how much effort one wants to put into it, and what one has to work with.
If security and even more privacy was my primary goal, then I'd stay off line. But even that isn't going to get you a free lunch in todays otherwise connected environment. For that, you need a singlewide in the mountains, by a river or lake, and some animals that can help you farm. I'm not even sure that is 100% possible, in today's world. Last I heard, D.B. Cooper was making a go of it, with his friend Bigfoot.