Convert Video/Movie files to MKVs with Embedded Subtitles

Because some of my TVs (i.e. Samsung) only plays subtitles when the file is MKV with embedded subtitles, I have to convert my mp4, etc. files into MKV and merge the srt subtitle files in MKV (My LG TV could just play any mp4 file with embedded subtitle via a command that I mentioned in my journal before), the best freeware to do this task is called HandBrake (don't use VLC, never work: just keeps looping the conversion into a <100k corrupted file despite claiming it has MKV conversion with embedded subtitle).