When I do os.walk('/') on a Linux computer, the entire file system is walked. On windows, however, I can only walk one drive at a time (C:\, D:\, etc.).
If this is a personal utility for one computer, and if you run XP on that computer, then you have the ability to mount secondary drives on to the file system of your main drive. This would give you the effect that you are enjoying on the Linux side.
I am guessing that the utility that does this is the same one that allows you to partition drives, but I'm not sure.
Ditto for win2k. right click 'My computer'->'Manage'->'Disk Management'
The only restriction is that both the root filesystem, and the one you want to mount within it have to be NTFS. (I may be wrong, but that appears to be true on my system.)
Still a moot point if this is to be widely deployed to existing PCs though. -- http://mail.python.org/mailman/listinfo/python-list
