" Swap file spread across 2 HDs = 1/2 the chance WinXP is using the swap file at the same time you’re using the HD"
With your above case scenario in which you have swap files allocated to more than one drive you’re working under an assumption that Windows will always make the right decision as to what drive to use to maximise performance/throughput. While I applaud your confidence in M$, I think it’s unfounded.
" Of course … you’re only using the swap file when you run out of ram"
That’s a common misconception…
No matter how much ram you have there will be programs that call the swap file by design. Windows will also use swap while still having abundant physical memory left as seen under performance tab of task manager.
You can install more memory and help minimise swap file use but it will still be used to some extent if available. You could disable swap if you have a lot of physical memory but sooner or later a program will call for a swap file and if it’s not there the system will crash or an out of memory error message will pop up.
The whole swap file ‘where to put excersize’ is so much of a non issue and waste of time fretting about too much IMO.
As for drive letter problems:
It seems you have another PC networked from the look of it with networked drives showing. You could dump more of your drives over to that machine and mount the drives to folders as you have already done so on main machine.
You could create a dedicated NAS box quite cheaply and use Raid 5 or such which will free up several drive letters and organise the confusing mass/mess of drives that you have.
You ‘can’ use drive letter “B” for physical HDD’s via a registry hack that I’ve read about in the past although I’ve never tried it. Google may help find it. It’s far easier though to map one of your network drives to that letter which is what I have done.