I have since followed the Windows 7 Help instructions and been into device manager and the appropriate Channel to select
ATAPI Cdrom which shows as
PIOMode4. Then I checked the "DMA enabled" box and clicked OK.
The window then refreshes and the "DMA enabled" box is unchecked again, so it looks like I cannot change it from there.
Then I tried uninstalling the Microsoft Driver for it, re-booted, and let Windows 7 install the driver again. But it still stays in PIOMode4.
The Pioneer website just says that the DVR-216D works with Vista using the Microsoft driver (no mention of Windows 7.)
Then re-installed XP and it is fine again (DMA is enabled) and the Movie that took 27 minutes to copy to HDD only took 7 minutes.

So the DVDRW and SATA cables are definitely OK.
For XP, the chipset driver I installed was from the Intel Mobo driver install CD, so it is an older version than the latest version I downloaded for Windows 7. I am not sure if using the latest chipset driver could be the problem.
Also there are later BIOS updates for my Mobo but the notes for them don't seem to have anything relevant to this problem.
Has anyone got any ideas that I could try seeing as it is OK with XP?
Many thanks for any replies.