The root cause of the problem is when an operating system is installed, be it a Windows or a Linux, a record of the partition number and disk bumber is kept so that on a boot up the boot loader knows where to find the system files.
Altering the boot disk order is playing a "cat and mouse game" with the boot loader.
The easiest way to get over this problem is
(1) Let Mepis disk be the first bootable disk. Verify it working properly.
(2) Add these lines to its /boot/grub/menu.lst
title Sausage factory dude said I can boot Windows as the 2nd disk
map (hd1) (hd0)
map (hd0) (hd1)
and save the file.
(3) Attach the Windows disk now. Make sure it is a slave if you run Pata disks.
Your Windows will now boot.
You can ask Grub to swap the disk order on-the-fly
, as indicated red
above. I have assumed your Windows is in the 1st partition of the 2nd disk, know to Grub as (hd1,0) as Grub counts from zero. Make the necessary adjustment to suit your case.
By the way I suggest users to chop off the hands fiddling the disk order in the bios to cause their systems unbootable. If they send the chopped hands to me I would have enough meat to open a sausage factory. I think the fiddling hands are surplus because if one uses Grub why then at the same time try to do its job.