A side note wrt to Java:   there are a couple of ways that current distros supply java.  Some ( e.g. Fedora ) do by providing you with gcj  and gcj compiled apps.   This is fine for many things, but if java code that uses newer java features then you may be stuck.  gcj is ( i think ) 1.4 compliant with some of 1.5.    ( see http://gcc.gnu.org/java/ )

Because of this and because I've found gcj to be slower than sun's java 1.5 or 1.6, I usually go with sun's java.   The simplest way for me to do that historically has just been to

- download sun's self extracting archive

- cd root; cd /usr/local
- execute the archive so it installs under /usr/local/<java_version>
- ln -s /usr/local/<java_version>  /usr/local/java

I maintain a softling /usr/local/java/jre/plugin/i386/ns7/libjavaplugin_oji.so  to /usr/lib/mozilla/plugins

and I usually keep /usr/local/java/bin  at the front of my path in .bash_profile.

Or, you get an rpm that plays nicely with the alternatives system and pick which java your system uses via alternatives.  This alternatives system is pretty slick and many distros support it.  Not sure if sun's java rpm supports it, but other packages do.   Google around.  A sample ( not sure if it is the best: I have not verified that the steps work as advertised ) is http://ccl.net/cca/software/SOURCES/JAVA/JSDK-1.5/index.shtml

Since Sun has re-licensed Java in a more friendly way, this should all get much easier going forward.   Things are pretty flexible right now, but the tradeoff seems to be out-of-the-box simplicity ( gcj )  vs robustness ( sun's Java ).   

best,
dan