...to add to my post above...
...it sounds like you have erased the two partitions already, but the partitions are still named Panther and Jaguar, so they will still mount that way, although the contents will be empty...
...using "disk utility" from the boot disk will allow you to remove those partitions, you need to go into the "partitions" section of "disk utility" and select the minus option underneath the the volume scheme diagram, left hand side, at the bottom...
...be sure to select the right partitions, or you end up deleting the actual partition that holds the current OS (in your case tiger)...
To enlarge a partition, you must delete the partition that comes after it on the disk, and then move the partition’s end point into the freed space. You can’t enlarge the last partition on a disk. You can see the order of the partitions in Disk Utility by selecting the disk, clicking Partition, and looking at the Volume Scheme list.
All data on the deleted partition will be erased. Be sure to back up your disk’s data before you begin.
To enlarge a partition:
From the list at the left, select the disk that contains the partition you want to enlarge, and then click Partition.
In the Volume Scheme list, select the partition beneath the partition you want to enlarge, and then click Delete (-).
The partition is immediately erased, leaving the space it formerly occupied available.
Resize the partition.
You can drag the divider at the bottom of the partition in the Volume Scheme list, or you can select the partition and then enter a value in the Size field.
If the enlarged partition doesn’t use all the space from the deleted partition, you can create new partitions in the unused space.
To create a new partition, click Add (+), select the new partition, and choose its name, format, and size.
Click Apply.
Disk Utility enlarges the partition and creates any new partitions.
andrew