Movies not displaying full screen on Vizio smart TV

I am trying to stream movies from my PC to my Vizio smart tv, its an E60-C3. I can view Serviio as a DLNA server, and it will find the movies just fine (a little slow sometimes), but when it plays, it plays it in a widescreen "box". It looks the same as if you were watching a non hd channel on your widescreen tv, like you are losing several inches of picture from the top/bottom/left and right. I know its not the movie because I can put it on a flash drive and it plays just fine on the TV.

What am I doing wrong?