I made some tests.
I removed the two filters you said, but the problem is still there.
I took image file and DVD and I tried to verify on another PC (different HW, different OS, different burner). It was ok, no hang. So I think it is not media problem.
Because this second PC is very old, Imgburn did not verify faster than 2x.
So today I tried to verify on first PC at 2x/2x speed. It was OK.
So I tried in order:
2x/2x -> OK
3x/3x -> OK (even if Imgburn verified at 2x/2x)
4x/4x -> OK
6x/6x -> KO
5x/5x -> KO
4x/4x -> KO
3x/3x -> OK (even if Imgburn verified at 2x/2x)
Do you think speed can be the right way to solution?
Another thing: when Imgburn is waiting for the device, if I try to "safely remove" USB external hard disk, nothing happens, that is "removal" procedure is also waiting for something.
I have not yet tried to use ASPI driver. Even if it says it's for win98, do you think I should try?