Lots of videos are in TP or TS files that are interlaced while others are in AVI(progressive). Instead of diving thru the menu on each video to activate/deactivate the deinterlacer, why not have it auto select by extension type? Even choose the method of deinterlace for each extension. A toggle to manually set the deinterlace should be on the interface or at least make it a user option to place it there.
Second, some videos have very large screens like the 1080p. When double clicked, most of the video is off the screen. A max initial video size would be nice, then the user can adjust it themselves.