First set an environment variable JAVA_HOME which 
points to the location of JDK. On my machine, it is
set to
JAVA_HOME=C:\Programs\j2sdk1.4.2

Also, include the JDK bin and the JWSDP bin in the path 
C:\programs\jwsdp-1.2\bin;C:\programs\j2sdk1.4.2\bin;%PATH%

Then double click on startup.bat in the 
C:\Programs\jwsdp-1.2\bin directory to start the Tomcat Web server.