Please find below the extension for Open Office..appears to be very good.
http://extensions.openoffice.org/en/project/pdfimport
How to install the extension:
Open Tools > Extension Manager and then browse to the file that has just been downloaded. Rest is self-explanatory.
After the extension is installed, you can open a PDF file just like any other word file.
Important: For the tool to be effective, open the pdf file using Open Office Draw. Using OO Write may not convert it properly. The resulting file will be saved as .odg
The document is now editable. Note that when you open the pdf ducment, it automatically converts it to .odg format, and there are no settings, etc. You can't change anything.