Making WMP default viewer for all vid formats

Been playing with opus, and i'm trying to get all my video formats to be played with wmp in directory opus viewer, not the default viewer... reason being i like the fact i can double click viewer and have it make the viewer be full screen, and when in fullscreen that i can double click it and it will bring it back to opus view. I've went into control panel auto play options and chose WMP to be default player, but when in opus. if i chose wmv. or avi. it doesnt show the WMP player, it shows the default player (which i believe from researching is the active x player? ) Can i make wmp be the default player for all file formats? (audio/video)
Thank you.

Just turn off the Movie plugin.

TY!!!! Awesome!

Too bad media commands that are system wide don't work. Like play, pause, next, seeking etc.

The WMP ActiveX control chooses to ignore them but they work fine in Opus's Movie plugin.