Actually, you can't resize 2K after it's installed. At least the partition the OS is installed on. 98 can't do anything with NFTS, still sees the drives, but doesn't know what's on them.
You could use Partition Magic to resize the drive and then make another partition for 98.
If you REALLY wanted to have a dual boot 98/2K machine, I would start from scratch and put 98 on first.
This is what I used to have:
2GB FAT32 98
2GB FAT32 2K
4GB FAT32 APPS (One directory for WIN98, one for WIN2K)
2nd drive (edit-forgot to add this earlier- I had both OS's sharing the swap file on this drive as well)
8GB FAT32 SHARED (Both OS's can see this)