It is true that a virus can theoretically enter a partition or slave harddrive. In my experience however, by far the majority head straight for the Windows, System32, and e-mail directories. It is another hurdle for a virus to jump a partition or separate harddrive, and they are safe unless there is a direct active path to those library files, you use it while your harddrive is infected, and the virus has instructions to seek it, if you follow my meaning. Most viruses are instructed to work in an existing operating system, and if your partition/harddrive is library only with no operating system it is extremely difficult for one to exist. A virus is a small program and can only do what it is instructed to do, and few if any are instructed to search out additional harddrives or partitions. That definitely holds true for spyware.
For several years I have set my units up both for myself and my clients with dual-boot harddrives, 2nd slave storage harddrives and dual-boot 2nd partitions, and I have yet for a virus or spyware to automatically jump the gap and invade.
I realize that there are those who will strongly disagree with me, but that's been my experience.
Give a man a fish and you feed him for a day;
Teach a man to fish and you feed him for a lifetime;
Then industry pollutes the water and kills all the fish.
