Drive letter changes using Computer Management hangs boot time

Summary;
Two HDD's, both bootable and partitioned (what should be C/E & D/F as the way it was with previous O/S's),
Two optical drives (what should be G & H),
Four slot internal USB Media Card reader (what should be I, J, K & L).

I just wiped, reformatted and reloaded XP Pro w/sp2. I disconnected my 2nd HDD and internal USB Media Card Reader (4 drive letters), but left my two optical drives connected before doing so. After the load, I timed this 'hang' and it was around 20 seconds (what it should be).
I then re-connected the USB Media Reader. I thought when I re-added the other bootable HDD it would bump the two optical drives and the reader down the ladder, but it didn't. Using Comp. Mgnt. I reassigned the drive letters for the 2nd HDD and the optical drives. Rebooted and timed the 'hang' portion. It went back to 45 seconds.

Why would changing drive letters other than the letter you are booting from make any difference? There isn't anything with those drives that Windows should care about since all the O/S files are in 'C'.

I tried changing them back (again using Comp. Mgnt.), but the 'hang' is still there. Now what?

(Hope all of that made sense)

 

Issue not solved.