This isn't really a bug report of imgburn, and it's not really about a bug in dvdd either...
I've posted my troubles in the doom9 forum, and you can read it here if you want the full story.
One helpful guy suggested that I reported the problem here since imgburn is based on the dvdd code. So if you ever get a similar bug report, you'll have a hint on what could be the cause.
Since I've fixed the problem, I can't really tell if the problem will occur with the code you have ported to your new app (thanks a lot for both of your great apps).
Well, lets take the steps to reproduce the behaviour:
1) Push pin 21 of your DVD reader into the back of the device, so that it can't be connected to the IDE cable
(I'm not to be held responsible if anyone chooses to reproduce this lame behaviour).
2) Run DVDD (any of the later versions will do)
This will cause the system to hang. If you try to access the device's properties in Control Panel>System>Hardware>Device manager>[Name of your DVD device] (the correct captions may be different, I have translated from a danish version of windows XP) you'll get the same effect, and if you insert a DVD media, you'll also get the same effect (this was my secondary DVD drive that I almost never use).
Repair the DVD device or get rid of it
The peculiar thing is that neither Nero, Isobuster, Alcohol 120%, SmartRipper or any other applications I've been using was causing the same problem, so it took me a great deal of time to figure out that it was a hardware error.