As a troubleshooting step, start Word in Safe mode and see if the problem persists.
To start in Safe mode: Exit Word if it is currently running. Hold the Windows logo key as you press R; in the Run dialog box, type winword /safe and press Enter (note the space before the slash).
If Safe mode works OK, then proceed to rename the Normal template (with Word closed). Also, you should troubleshoot for poorly designed add-ins; see
http://office.microsoft.com/en-us/support/why-cant-i-start-my-office-2013-application-HA104011864.aspx.
Stefan Blom, Microsoft Word MVP