CD/DVD drive Error message, wont burn?

So my 1TB desk top is about full of High def High res RAW files & so is my 1TB Western Digital External Hard Drive.

My solution was to start burning all my LARGE RAW files to DVD to clear space again; PROBLEM is I’ve tried 3 different ways to burn ANY file to a DVD and get same ERROR message. Click on Error message & Mac doesn’t know what it is? Bottom line I can’t burn & clean up my much needed space for my Photo work…

I tried Burn to my Toast titanium system, to a desktop burn folder, & export a version and burn to disk… all 3 ways get same error message & does nothing just stops and ejects????

Error Message: “The drive reported an error: Sense Key = Medium ERROR / Sense Code = 0x0c / Write Error” ????

NEED BIG TIME HELP PLEASE… Thanks Dave