Hi,
For the "g:" you can open the file plugins/hikashop/google_products/google_products.php with a tool like notepad++ and use its "search and replace" feature to replace g: by nothing and apply to the whole file and then upload back the file to your website via FTP.
For the
<![CDATA[[/code] and [code]]]>
these are separation elements for XML file. It's standard :
www.tutorialspoint.com/xml/xml_cdata_sections.htm
Normally, something processing XML files should be able to take them into account properly. So you should not need to remove them. But if you really need to remove them, you can use the same technic as for the "g:"