What else do i need to run wideshow

You have to make sure that Java is installed on your system.
To ensure this you simply can type "java -version" on the commandline.
If it prints something like this:

java version "1.6.0_10"
Java(TM) SE Runtime Environment (build 1.6.0_10-b33)
Java HotSpot(TM) Server VM (build 11.0-b15, mixed mode)

then everything is fine and you can start using wideshow.

if you encounter something like can't find command "java" or so then you have to install it.
If you are running Windows you can go to the following site and download a simple installer for java.
http://www.java.com/

when you running a linux based os please refer to your distro'r documentation how to install java.
On ubuntu it goes like this
"sudo apt-get install sun-java6-jre"