Maybe below steps will help you:

1. Install JDK1.5 Full, latter is recommended
- J2SE Development Kit
- JRE (Java Runtime Environment)

*J2SE Development Kit 5.0 update 9 - JDK1_5_0_09 (jdk-1_5_0_09-windows-i586-p)
*J2SE Runtime Environment 5.0 Update 9 (will install while installing JDK1_5_0_09) - jre1.5.0_09
* Install both at the same directory! (C:\Program Files\Java)

2. Install Apache Tomcat (jakarta-tomcat-5.0.28)
*Installing & Setup Instruction - http://tomcat.apache.org/tomcat-5.0-doc/setup.html

a) Follow the instruction and install (at default directory).
b) Select directory installed JDK1_5_0_09 for setup JVM (C:\Program Files\Java\jre1.5.0_09)
c) Start the Apache Tomcat service.
d) At IE browser, type http://localhost:8080/
e) The Apache page will diplay, meaning successful installed. Congratulations!