What driver do i need to read a hd dvd on my LG GGC H20L?

Have you gone to the LG web site and looked for the drivers? Here are a couple of links that may help you.

http://www.dvd-replica.com/DVD/data-2.php

http://www.gromkov.com/faq/faq2004-0056.html

Yes and the drive has been discontinued by LG. I have the version installed that is available at their website. Could it be a conflict issue with multiple programs running simultaneous?

It could be that you have the file but can't be read because it may be corrupted , so the best option would be to do a backup or download a newer version.

?? You can not play DVDs, or Blu-ray disk, or Both.

Get a Blu-ray program and it should read both.
I use Cyberlink
http://www.cyberlink.com/products/powerdvd/overview_en_...
and total Theatre
http://www.arcsoft.com/totalmedia-theatre/

There are some others, Free ones are rare do to the codec being a liciened product.