You would not lose your data as a result of a simple reinstall of OS X, unless you made a choice to go into Disk Utility, and erase your drive first.
There's no reason to do THAT, as you simply screwed up your system by removing a major piece of the system (the "wheel" user --- used internally by the system)
And, reinstalling OS X does a re-load of all the system components. It checks during the install that all components are complete, and in the correct location.
If you have spent some time around MS Windows, it is similar to a repair install of Windows - a good first step in getting Windows to work properly when you have problems with a Windows system.
So, reinstalling OS X basically "repairs" the install of OS X that was already in place, including all your own files, settings and apps that you might have added to your Mac system. THOSE parts are not affected, just the basic system is reinstalled.