Bug reporting html form problem with reading OS automatically

I am preparing a layout for a bug reporting page, such as the one at http://bugs.sun.com/, however mine is quite simpler, so far.

As part of the controls I intended to have a control which automatically reads the Operating System using Java Script code, which I snipped off a website, however, it does not seem to work here. I tried it on Mozilla Firefox, IE9, however when I select the button nothing happens, what am I doing wrong?

Is it possible to detect the version as well using Javascript (JS)?

The HTML validation service also displays some validation errors, I have not yet corrected all of them.

Bug writing help at https://issues.apache.org/bugwritinghelp.html.

Operating system script at http://www.javascripter.net/faq/operatin.htm.

Getting started with Javascript tutorial at http://www.w3schools.com/js/default.asp.

NOTE: Signin using facebook does not seem to work within this forum. I am using Google Chrome.

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