If you are dead set on getting a DVD-ROM, then you should get the LiteOn SOHD-16P9S (it was going for $20 USD at Newegg recently; other drives based on the SOHD-16P9S include the Sony DDU1615, Teac DV-516G, and NEC DV-5800D). If you must get a DVD-ROM to scan, the 16P9S is probably the best scanner of them all (there's a big improvement in PIF scanning over the previous LiteOn DVD-ROM models). That having been said, it still won't match the scanning accuracy of a proper DVD-writer like a LiteOn or BenQ.
As for copy protections, I don't know if anyone has tested that with the 16P9S. All the previous LiteOn DVD-ROM drives were good for it, so my best guess is that the 16P9S would be fine as well.