I'd have a look at this same/similar question: How to run Mac OSX within Windows Virtual PC
Jonathan Sampson answered:
Can you run OS X on Windows? Yes,
apparently you can with PearPC.
Is it legal? Well, that is another
question on its own.
While it is possible (which is what
you asked), there are certain
limitations:
While the CPU emulation may be slow (1/500th or 1/15th), the speed of
emulated hardware is hardly impacted
by the emulation; the emulated
hard-drive and CDROM e.g. are very
fast, especially with OS that support
bus-mastering (Linux, Darwin, Mac OS X
do). A lot of unimplementated features
are fatal (i.e. will abort PearPC).
Timings are very still a little bit
inaccurate. Don't rely on benchmarks
made in the client. PearPC lacks a
save/restore machine-state feature. No
LBA48 (but LBA). Currently no support
for hard disks greater than 128 GiB.
Disks > 4GiB are not tested very
well.