Java EE (Java Enterprise Edition) General Discussion

HI everyone. I'm new to these boards and java. I was hoping someone might be able to help me with a part of my Apache Tomcat installation.

I'm trying to learn JSP and to do that I downloaded J2eSDK1.4 and Tomcat server. I installed them both. Part of my Tomcat configuration requires that I establish an environemnt variable named JAVA_HOME and it (as the book says) "points to the installation directory of Java; for example, that might be c:\jdk1.4". Now I installed the SDK and it created the following directory "c:\Sun\AppServer\" with the following folders underneath: bin, config, docs, domains, icon, imq, jdk, lib, pointbase, samples.

What should my environment variable be set to? I tried:
c:\Sun\AppServer\
c:\Sun\AppServer\bin
c:\Sun\AppServer\jdk
c:\Sun\AppServer\jdk\bin
c:\Sun\AppServer\jre
c:\Sun\AppServer\jre\bin

But all the time when I try to start the Tomcat server I get the following error:
The JAVA_HOME environment variable is not defined correctly.
This environment variable is needed to run this program
Using JAVA_HOME: C:\Sun\Appserver\
The System can not find file -Dsun.io.useCanonCaches=false.

Can someone tell me what I may be doing wrong? Did I not set up my environment varaible correctly? I'm trying to do this on a desktop running Windows 2000.

Thanks!