Saved this from an Anonymous poster a while back, I've yet to try it myself. It seems to be pretty straight forward, without a lot of geekspeak. Hope it helps someone:

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If your going to upgrade to Win2K take this opportunity to upgrade the hard drive at this time (i.e. a _much larger one_). Use the current HD as a second HD accessible via either Linux or Win2K. i.e. A 2 GB Dos partition that Win2K and Linux can use to swap files with.

Caveat #1:
Win2K _must_ be installed on the HD first with the HD either new or erased (no partitions). The reason for this is that Win2K creates a second partition of 8MB to keep certain files in during the install process.

1) Install Win2K onto the HD. Select a partition size that you feel is
appropriate.
2) Install Linux.

Option 1:
If you intend to use lilo to boot Win2K then you are done. :o)
Go to www.linux.org and in the search dialog type in Dual Boot and find a topic on adding a selection to lilo.conf for booting windows on a dual boot machine.

Option 2:
If you intend to boot Linux from the Win2K boot manager you will need to do the following.

1) Boot linux and create a bootable floppy. (You should already have done this as it is a real good idea!)
2) As root run the following command:

dd if=/dev/hda of=bootsect.lnx bs=512 count=1

This will copy the Linux boot sector to a file named bootsect.lnx in the /root directory (or where ever your flavor of Linux goes when accessed as root)

3) Install a blank floppy in the system floppy drive and execute the
following:

mount /dev/fd0 /mnt/floppy
mcopy bootsect.lnx /mnt/floppy
umount /mnt/floppy

Remove the floppy.

4) Install the boot floppy and reboot the system to make sure that the boot floppy boots Linux correctly.
5) Remove the floppy and reboot the system into Linux.
6) In a terminal window type the following:

lilo -U

This will disable the lilo boot loader.

7) Reboot the computer
8) Login to Win2K.
9) Double click on the 'My Computer' icon.
10) Insert the floppy containing bootsect.lnx into the floppy drive.
11) Double click on the A:\ Drive icon.
12) Right mouse click on the file in the floppy drive and select copy.
13) Close the A:\ window and double click on the C:\ icon.
14) Place the mouse pointer any where in the C:\ window and click the right mouse button. Select Paste.
15) This copies the bootsect.lnx to the C drive root.
16) In the C:\ window select boot.ini and open it (You may have to open 'File Options' and unselect 'Hide System Files')
17) Add as the last line the following:

C:\bootsect.lnx="Slackware Linux"

Save the file and reboot the computer.

At the Win2K boot selection window select 'Slackware Linux". Linux will boot.
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