You should *NEVER, EVER* mess with partitioning on a disk without first making a complete backup, or better still, a complete backup and an image backup as well. If anything goes wrong during disk partitioning, it's at least possible that you might not otherwise be able to recover the disk contents affected thereby. The first step in moving, resizing, or otherwise messing about with disk partitions should ALWAYS be a backup/image backup.
HTH,
--Ed--