That tells me two things:
1: You are using Windows; Linux gives a different error message.2: You haven't got your PATH set up correctly.Everybody gets that problem. That is why it is the first problem quoted in the "problems" link I sent you. Follow the instructions in that, and follow the link to "setting the PATH permanently." Make sure to set it permanently, and don't believe them when they say it's "optional."
It will be a lot easier if you remember where you installed Java; that will be the same directory as you told NetBeans when it asked about JAVA_HOME or similar. The PATH entry starts with the drive letter (usually C) and ends with
bin.
You don't need lots in your CLASSPATH, but you might as well check it when you set the PATH. It should have .; or ;. or ;.; in it somewhere, where the . means "current directory." You usually have to change your PATH and don't usually have to change your CLASSPATH.
[edit]Add this
link which tells you about setting the PATH.[/edit]
[ November 05, 2008: Message edited by: Campbell Ritchie ]