CSS Formating w/o Absolute

Hello,
I've onyl used CSS for two weeks and needed some advice from the pros. The
website I maintain is
www.baum-hs.eu.odedodea.edu
I'm wondering the best way to keep all the boxes aligned without the use of
the position:absolute because sometimes it does not lineup properly with
Mozilla. I see auto and relative as choices but have no idea what they
actually do or mean.

Also, any pointers as to why this page looks like doo-doo on Mozilla? I've
made this page to meet a deadline and 98% of the browsers used to test this
is IE. I want to make it a lot better and a lot nicer looking since the
people who wanted this up only wanted to see certain things on ther Internet
regardless of aesthetic appearance. Thanks in advance.

--
Radley