You have to change the “compatibility settings” for JabRef to “Disable scaling for high DPI settings”. Further information is available at https://www.microsoft.com/surface/en-us/support/apps-and-windows-store/app-display-issues?os=windows-10
Further reading: https://github.com/JabRef/jabref/issues/415 and http://discourse.jabref.org/t/jabref-3-6-on-hires-laptop-screen-messed-up/277.
You can directly use the references in Word’s internal reference manager.
Short explanation: Export your bibliography in XML format and replace the Sources.xml in
Long explanation: see Using JabRef references in Word document.
Another option is to use Bibtex4Word.