You must not know that much about Windows.. You can break all of this out yourself and have windows configured however you want it... Which is exactly what you do when you install a Unix system. I can install redhat and have a volume named c:\ and have everything reside within that file system. With windows2000 the idea of having to name volumes c:\ d:\ went away. For instance I have volumes on my machine that are named by what they do, and I can access them by that name, not d:\, e:\, etc... Just like in unix. There is nothing wrong with the file system in windows. And this is perhaps the craziest thing that I have heard from a windows basher.
The problem with Windows is not about viruses, worms, firewalls, or even bad code. It's about bad design choices. It's about having the entire OS installed on one monolithic C: drive instead of having a distributed file system where you can have /, /tmp, /usr, /var, and /home mounted on separate partitions with different execute permissions (noexec, nosuid, nodev, etc). It's about every user on the system needing Admin privileges to run basic applications because the directory layout was designed for a single-user environment (and not particularly good even for that). It's about things like this.