Hi Yuki.
Why not do something like this. I have changed the way the course view summary/info works on my Moodle 1.9 site HERE
#site-index.course .coursebox .summary,
#site-index.course .coursebox .info {
width: 98%;
margin: 0 auto;
}
To set this up on your Front Page go to...
If you go to Administration > Front Page > Front Page settings
and then make the Front Page use Courses and site news or Site topic and Course.
Then whatever you add in each Course summary description be it images or text of both theme will show up like the example on my site.
Mary