Opening a new instance of OSX on the same Macbook Pro?

There are a number of applications specifically for the purpose of distraction-free writing. You can Google for them, but here are some links to start:

http://thenextweb.com/lifehacks/2011/08/08/the-top-5-minimalist-writing-applications-for-the-mac/

http://lifehacker.com/5689579/five-best-distraction+free-writing-tools

http://www.gradhacker.org/2012/01/25/even-more-distraction-free-writing-tools/

http://www.thebookdesigner.com/2011/07/7-distraction-free-writing-environments-for-authors/

 

Not unless you want to have two OSX partitions on your HDD /SSD.

That's about the only way I can think of to achieve this, and ALT+TAB won't work...It would mean a re-boot between the two.

 

Create a new user and set the Parental Controls and only allow one or two applications to be used.

 

Are you referring to "new instance" of OSX along the lines of the virtual workspace available in Linux where you can be looking at/using your desktop and hit a keystroke (CTL + right arrow or similar) and go to a new desktop that appears like no applications are currently running but all apps are available to use just like the original desktop, while all your applications previously open and in use are still running on the other desktop?

 

https://discussions.apple.com/thread/4139762?start=0&tstart=0

http://en.wikipedia.org/wiki/Virtual_desktop

 

I second this. A new user account that you log into, in which you can only access one app and no internet would be the way forward. Virtual Desktops or VMs of OS X are completely unnecessary.

 

Very true. I mis-read the question the first time and thought the OP was asking about needing a clear workspace without all the other apps that may be open appearing. Wanting to self limit to one application is more of a personal issue over self control to not be distracted by the availability of other software so I'll defer to others to help with that part.