While I sincerely appreciate both of these responses, unfortunately neither help. I did purchase the retail package but it did not include Nero. And even if it did, I wouldn't be using it; due to the bloat of nero over the last several iterations I use a number of freeware solutions.
But that just raises the question.... as far as I can tell in the software I'm using it isn't a soft-setting. To all appearances this is a problem at a more basic level. Opti Drive Control reports that the maximum speed for a DVD read operation is 6x. This software isn't interfacing with anything else (so far as I know). I am by no means an expert, but it seems to me this is an issue either with the hardware itself or with the drivers Windows is using.
As I said, the drive itself is brand new. I simply replaced a Samsung SH243 (or something close to that). A simple drop in replacement, not with a fresh system build and Windows install. All of the same software with the Samsung worked just fine, it's just since swapping in the new drive that things slowed down dramatically.
Any other suggestions?