I archived hundreds of DVD's a year or two ago. I used various brands of DVD-R's, but it turns out that every Ritek 8X I burned now has CRC errors when I try to read it on my NEC ND-3520AW. I originally burned the discs using this drive. When I try to read the discs using my Samsung TS-H352A (a DVD-ROM drive), it can read about 90% of the Ritek's without a problem. How can I recover the remaining discs? Is there a drive with more powerful or accurate lasers?