No, you cannot run OS X on a PC.
Leopard, OS 10.5, contains a program called Boot Camp, which allows you to create a partition and install Windows.
Technically, Macs with Intel processors are very similar to their PC counterparts now, but Apple hardware are the only machines licensed to run OS X, where regular PCs are not.
If you want to run Windows on a Mac, Boot Camp, or an emulator, will work just fine. That way you can run both systems side-by-side. You could turn a Mac into a Windows-only machine, but that defeats the whole purpose of having it.
Hope this helps.
-BMF
Can you install a windows OS on a Mac or OSX on Windows? I know you can run emulation software to run windows in OSX, but I don't understand what makes Mac's so different from PC's that you couldn't just install windows directly and boot from it? Does the Mac contain an apple exclusive hardware/software part that only allows apple OS's to be installed? Thanks for any help.

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