If you are going to use the NT (2k & XP also) boot loader, I would do this:-
1. Create primary partition using fdisk for win 98 & install win 98.
2. Boot from win2k server install CD, and use its tools to create a second partition (this will be logical drive in extended partition I believe) to install 2k server in. Install 2k server.
3. Boot from XP install CD, and use its tools to create a third partition to install XP server in. Install XP.
However, I would always use a boot manager and keep the operating systems independent (use primary partitions). The above scenario has all three o/s dependent on the one (C: drive) boot sector. anything happens to that, you've got problems will all 3.
So, my alternative. Download boot manager from
(one I use - free for personal use).
1. Install XP first (as has disk management tools to let you create up to 4 primary partitions on one drive). Just create one partition big enough for it during the install, and leave rest unallocated.
2. In XP, create 2 more primary partitions for 98 and 2k server (obviously 98 must be FAT or FAT32). Install boot-us. It has tools to hide partitions - both windows and dos based (you'll need to hide partitions with operating system installed while you install others, so each puts its boot sector in its own partition). So, set XP partition to be hidden.
3. Install 2k or 98 next. Install boot-us here too, and hide this partition.
4. Install final operating system, install boot-us again, unhide all partitions and set up boot menu.