|Are you willing to start from scratch? Obviously 2GB is WAY too small for XP plus it would be better to format using NTFS. Not only that, but it's generally best to have the older OS installed 1st.|
What I would do is completely wipe out all partitions, then create at least 2 new ones, one for W2K & one for XP. Actually, 3 partitions would probably be better - the 3rd partition would be for data storage & would be accessible from either OS. If W2K isn't going to be used much, create a small C partition, say 10GB. The XP partition should be considerably larger, maybe 60GB? The remainder would be the storage partition.
Start by installing W2K. Once the installation is complete, boot into W2K, insert the XP disc in the drive & wait for the popup. It will ask if you want to upgrade (recommended) - do NOT do it! Instead, click advanced & direct XP to install to the 60GB partition. The dual boot configuration will be setup automatically.