Hummm....first off the subtitles are in very bad English. ^_^ That aside, the guy behind MediaCoder was working on a font size script for the program, but he seemed to have abandoned it. Check out these posts on MediaCoder's forum:
MediaCoder :: View topic - Subtitle size
Below link of a post a year ago:
MediaCoder :: View topic - Big subtitles! PLEASE HELP!
So, sorry ah.ni.may, I would just go with the default font for that. To go back to defaults, open up MediaCoder, go to the subtitle tab, click on the "Advanced" button, and then click on the "Revert" button on the pop-up window. Conversion A looked fine to me, and I beleive that is the default settings.