Fix 2 bugs in the error paths of the ds3d.c test (coverity).

- Fix ref counting.
- Use This->window instead of QI in NSContainer_Release.

Fix DVD_ReadStructure to reflect what Windows actually does, not what
Microsoft (incorrectly) documents it to do and not what the DDK
headers (incorrectly) suggest it does.

Programs that are written specifically for 2000 and xp don't bother to
set the primary buffer format because it's a noop.  However wine is
patterned after win9x and DirectX 7 or earlier which has a real
primary buffer and expects the program to change the primary buffer
format if necessary.

ExitWindows kills all current processes and that creates a race with
newly started processes. Instead, simply exit and let the new process
create a new explorer.

Remove bogus release of NULL pointer code found by Coverity.