Yes. I am saying that there is no such option in mplayer.

I'm not sure you entirely understand what the mencoder executable does. It is a transcoding program, which allows you to create video files with parameters you set. You'd feed your high rate video files into it and specify options to create the output video you want.

It might be considerably easier for you to search for tablet_encode and/or the Video Converter software published by Nokia (Windows) -- feed it your high rate video files and get one output that has been optimized to run on the tablet. Either of those solutions will ultimately do what you want -- create a video file that plays on your tablet. As a side bonus, you won't need to eat up 2.25 gigabytes per hour of video in storage on your tablet, either.