Is it possible to export from the HTML table report?

I have the script to run but don't know where to insert it.

If you are trying to export to Excel format, that can be done from the submission view of your account:

http://www.jotform.com/help/44-How-to-Export-Form-Data-to-Excel

However, depending on what format you are trying to export to, there may be different methods.  Would you mind explaining a bit more about a how you are trying to export your data and in what format?