I would boot the Live CD and then use the partition manager to label the
disks. Do not access the disks with a file manager first or you will be
mounting them and you don't want that. If a disk icon appears on the desktop
then you can right-click and unmount from the drop down menu.

You might want to take note of the Linux drive designations (sdb1, sdb2,
etc.) and disk or partition size first so that you don't get them confused
before you re-boot and use the Live CD.