I've just installed arduino-0022 on Gentoo Linux.
It looks great except for the toplevel menu font, which is extremely small (barely readable), and which I can't seem to control from the preferences.
I've edited the preferences.txt and theme.txt files, and found that the font settings found there do not effect the toplevel menu (File, Edit, Sketch, etc...).
I assume this is a java setting managed outside of the arduino configuration.
I'm looking for help on finding where this font selection can be modified.
Try downloading another Java application and see if you get the same results. If so, it's a Java problem.