For both groups, I'd start at Javapassion.com and see if anything there
matches your needs.  Sang Shin is an employee of Sun and a researcher
there.  He maintains on-line classes for various Java related topics,
including the Java language and J2EE.

http://www.javapassion.com/

Hit that first, then if you feel you need more, look for more expensive
or involved solutions.  You could probably send a group of Java
neophytes directly to Shin's Java Intro course webpage and let them
learn on their own.  The advanced group might be more problematic, you
may need something more for them.

Here is Mr. Shin's biography:

http://www.javapassion.com/SangSchedule.html#Bio