Hi jrbuergel,
Before doing the fresh install of Mandriva 09, did you prepare a new partition for it, or make any assumptions about where it would be installed? Did you consult Mandriva 09 Installation Guide(lines) at the Mandriva website? Or, at least try to find such guidelines?
A good set of guidelines to follow in the future is from member saikee's links in his signature where he has a model for many multiple partitions of Linux and other OSes - setting up, etc. See:
A simple Howto for installing and booting 145 operating systems in a PC, and the other links in saikee's signature at the end of the post.
Since you were doing a fresh install of Mandriva 09, I doubt what you experienced has anything to do with M$ code - I would never give them that much credit for all the crappy software they have produced (OTOH, the Singularity OS project is focued on making a new OS completely independent of Windows code, and at least someone in M$ is doing the right thing for the future to save their bacon!).
-- Tom