All of the evidence leads to a failing drive. We could continue running fixes till we're blue in the face, but when a drive fails...it's done.
Usually, in this case, if you have LG support repair it, (if not under warranty), you'll pay an arm and a leg to replace the burning mechanism. Same type of stuff I went through, except my issue was more VCR/DVD recorder problem.
Price of new drive: $40-80 USD
Price of mechanism: $60-260 depending on brand popularity
Cost of replacing mechanism (tiresome): $60-200 depending on experience of techie.
As you can see, a new drive is the best option.
I'm sorry it came to this, as I wouldn't recommend you to pay anything unless if necessary.
Let me know what you do.