Eh, both have their advantages and disadvantages. For example: Mac is much more expensive than most PCs (that could be better than it) and some PCs aren't as good as Macs. In my opinion, Windows. Preferably Windows 8 because most features seem simpler and it has all the cool apps.
There is no logical reason I know of to choose OS X over Windows, besides the common "Mac looks better" argument, which in the end just comes down to personal preference. Windows is superior in every form other than boot time and file system searches.