I know that it is possible to install software on a MAC so that PC software works on the MAC computer. Is the opposite possible?

Mac software just won't run on Windows (or Linux). The end.

I'm also not aware of any emulators, like Parallels or VirtualPC for doing the opposite.

There are some projects out there, such as OSX86, trying to get OSX to run on a windows computer, and there is some success, but the legality is weird, and even if it works [seems maybe 50% at best, for people who know what they're doing], then it usually is buggy.

Best option would be using an Intel based mac to run windows and OSX, plus linux if you want. (I prefer dual boot, though emulators can be nice in some cases, too.)