I've used MC with Parallels and was left somewhat wanting. Running MC inside the VM works just fine, but Parallels choked on MC in its "Coherence Mode" (which is the mode where Windows apps look, feel, and run like OSX native apps). Other people have used it this way successfully, and have even used Theater View with the new DirectDraw acceleration built into the VM software turned on (it isn't by default). It seems to have something to do with the hardware. The Intel Macs with Intel graphics (the cheap, non-pro, ones) seem to work well. The MacBook Pro and MacPro with ATI graphics hardware seem to have more issues. This is likely just because most development has gone towards the more popular platforms, but it was quite buggy in my experience.
I personally was VERY disappointed with Parallels. It just felt very beta and unfinished, and for something that digs so deeply into the OS it really needs a better uninstaller. You might very well have better luck running it with a "real" guest OS image -- I was using my BootCamp partition as the guest OS partition -- but I was left unhappy. Their user support is terrible -- if you asked questions the answers all seemed to be "don't do that" or "your stuff is broken" -- and the help was extremely difficult to find. The worst part was that it was impossible to uninstall the "hooks" that Parallels puts into your BootCamp partition unless you do it from inside the VM engine. Of course, I didn't know this and the trial expired. Opening Add/Remove Programs and choosing Uninstall on Parallels Tools from inside BootCamp, just responds that you must do it from inside the VM (which you can't if the trial is over).
That said... I haven't tried it yet, but I've heard MUCH better things about VMWare Fusion. One of these days I'm going to take the plunge, but I'm waiting a bit right now... Too busy and too much to do to mess with it right now.
I should say... Using BootCamp IS windows, and works perfectly well on my Mac Pro. On my MacBook Pro I do have some weird issues in BootCamp, but nothing too serious. I actually use it in Windows about 1/2 the time, and it works great.