As far as getting a smaller font goes, are you running in a virtual terminal or in a terminal emulator under X-Windows?
For the terminal, try passing the vga=ask option to the kernel when you boot up, you will then be prompted for the video mode to run in, in characters per screen.
Under X, try running it in konsole from KDE; you can then reduce the text size with the menu options. Other terminals probably offer similar features.
To increase the fps, look first to the “-fps” option of mplayer, and then try changing the audio driver “-ao help” if that doesn't work. You might also want to look at the “nice” and “renice” commands, and possibly changing the value of /proc/sys/vm/swappiness. It's a bit difficult to give precise advice on what to do here, as I don't know what the bottleneck is on your setup, or even if it's just a settings problem.
Hope that helps,
— Robert J. Lee