yeah that path setting will do fine - that'll give you access to java, javac and javadoc from any directory.
But you may wish to add the directories of any .jar files u wish to use, be they Java's own or secondary sources, to the CLASSPATH, to make sure that Java knows where to find these classes, without it you may find some methods you use cannot be found, you'll get compile time errors all over the shop!
Cheers!
Relisys