Hey, Fielong, are you still trying to convert any videos? If so, then try XMedia-Recode. It will allow you to choose which audio/video/subtitle tracks you convert, and how you want to convert them. I’m sure it has a “profile” for PSP, meaning that you can use its default PSP conversion settings without problems. Just make sure to set the “subtitle mode” to “render”, which will make the subs a permanant part of the video stream.