MKV (Allows for multiple subtitle tracks and better audio).
If you want a smaller file size without losing quality, x265 is better. It is a modern compression standard that makes a 500MB file look as good as a 1GB x264 file. mebeforeyou2016720pblurayvegamoviestomkv better
1280x720 pixels. While lower than 1080p, it is often the "sweet spot" for mobile devices and smaller laptops. MKV (Allows for multiple subtitle tracks and better audio)