If you use the PC for communication, such as email, Web, Skype, then there is no reason to keep Windows. Those things work fine on Linux.
If you need to prepare an occasional document, use online services - Google Docs is free, MS Office Online is free. These work on any OS.
If you need the computer for serious, professional work, then you use the OS that runs your business software.
I love Linux mint 17.2. Fastest OS I ever used.