Dual Boot , WinK2 Pro +98SE,

Simple answer, but not a good one for you. Win2K, WinNT, XP and Linux all preclude adding different operating systems once they are already installed. To install 98 on a 2K machine you will have to First: uninstall Win2K, install Win98(se), leave anunformatted space on the harddrive or unformatted or Fat32 formatted second drive, then install your Win2K. Second make sure all of your hardware, including systemboard harware, such as an ATA66/100 header, onboard sound and video...etc. are compatible with both OS's.
Hope this helps ... H
PS: you can add OS's by booting with a floppy but the dual boot screen/function will not be available and you may loose all of your previous information and files, but you already knew this. :-)