Wow, this is a really active forum...
I am figuring this out on my own, but I figured I'd go ahead and post my findings so others might benefit from it one day.
Anyhow, I uninstalled the virtual drive, and iTunes can now burn CD's again.
As I had mentioned before, I saw that other drive virtualization solutions out there can cause the same problem, and when you run the iTunes diagnostics utility, it even said right on it that virtual drives can sometimes interfere with iTunes. Unfortunately, at the moment, I have no drive virtualization software, and I was really looking forward to having it, so I'm gonna play around with some other free utilities. I read that Daemon Tools has seen this problem enough times that they have a fix for it that allows you to still have virtual drives without losing any normal drive functionality in iTunes or other programs. However, I have no desire to pay for virtualization software - it's a nice toy at the moment, but I don't need it often enough or for any moneymaking purpose, so I'm gonna try out a couple other free virtual drive softs.