That looks to me like Diskpart has assumed (ASS U ME d) the drive letter
assignments rather than determined them from the registry.
When in safe mode, diskpart is obviously able to access the registry so
it correctly sees that volume 1 is not assigned a drive letter, that
volume 2 is assigned "C" and that Volume 3 (the normally hidden recovery
partition that most other OEMs, other than HP/Compaq, hide out of sight
of the consumer) has been assigned the drive letter "Q", suggesting the
OEM in this case is HP/Compaq.
When you boot from the DVD and use the recovery/install console Diskpart
either can't access the existing registry files on volume 2 or else is
ignoring such a potential source of confusion and simply shows the
standard drive letter assignments (probably based on the same rules that
MSDOS would use).
When it comes to installing windows NT5 onwards, you can create any
partitions you like on as many drives as you have and pick any of the
disk volumes (space permitting) into which to install the OS. Since
there's no benefit whatsoever in choosing a less obvious drive letter for
the system partition, the normal practice is to create a drive C suitably
sized for the job and choose that as the disk volume to install windows
onto.
With windows 2000, there's a great big 'gotcha' if a card reader is
present and enabled when installing windows. The installer unconscionably
pre-assigns drive letters C, D, E & F to the card reader slots and you
land up with windows installed onto the first active primary partition of
the hard drive which has been assigned the drive letter H.
The solution to this problem is simply to disable the USB interface in
the BIOS before re-running the installation. I believe the installers in
winXP and later solved this problem but for anyone trying to resurrect a
win2k machine that *now* has a 4 slot card reader fitted, it's important
to either disconnect it or, more simply if you plan on using it after
finishing the initial installation, just disable the usb support in the
cmos setup for the duration of the installation process (at least to that
point when it executes its first reboot from the HDD or SSD).
The only drive that you can't edit the drive letter assignments on using
DiskManager is the system drive (normally drive C). If you've somehow
managed to land up with windows installed to drive D, the only way, short
of a full re-install and paying attention to what you're doing, is to run
a third party utility, usually from off its own boot media (eg Paragon
Disk Manager rescue CD/bootable USB drive).
HTH & HAND :-)
--
Johnny B Good