If you’ve tried Learning With Texts for Japanese, and I recommend you do try it if you haven’t, you’ve no doubt found that the text window uses the same sans-serif font as everything else and is kind of painful to read. Here’s a replacement stylesheet that will fix that. You’ll need the MS Mincho font installed on your machine, which Windows computers have by default, don’t know about Macs.
Save this file into the css subfolder in your LWT installation directory, overwriting the existing version, and enjoy readable text.
Lan'dorien's Mysterious Journey 
While MS Mincho is not available for Mac, a similar font, Hiragino Mincho Pro is. I personally prefer the non-serif lines of Hiragino Kaku Gothic Pro. Since fonts can be a really personal thing, I recommend checking out this Wikipedia page that shows how every font available for Mac is rendered on screen. It’s great way to pick out a font that works for you.
http://en.wikipedia.org/wiki/List_of_typefaces_included_with_Mac_OS_X
I’ve added this font to the stylesheet now. Also changed the background colour to tan so it isn’t so stark. Reading on the computer is hard enough without turning the contrast setting to “stun”.