If you are running Windows on VMware, Parallels or Virtualbox, the only thing that matters is that you are running the required version of Windows in that VM to support the software you want to run (LR 5). The underlying operating system (Mac OS X in your case) is irrelevant.
You do have to make sure that the version of Parallels/VMware/Virtualbox you have supports you host operating system (10.6).
If you are not overly technical, I'd recommend either Parallels or VMware Fusion, whichever you can get for the best price.
I hope that doesn't confuse things too much....