Yes, this is correct. This Microsoft utility automatically repair issues that block program installation or removal because of corrupted registry keys. If this didn't uninstall the HP software completely, then go into the Control Panel, uninstall a program. I will provide a HP document on performing this step here.
You only have one Officejet 6500 printer right? If so, then please uninstall both drivers.
If you have any further questions, please let me know.