After the drive has been partitioned, it needs to be to formatted which is easily performed with the "Format" button.
But before leaving DiskDrake, first make a note of how the partition is named.
As you already know, partitions are used to divide a disk into one or more distinct areas.
Whenever you see a device name such as "hdb1", that means it is the first partition of a disk and is also the "active" partition.
Since the Linux OS doesn't need to be installed onto an active partition, it is usually seen as "hda5" when sharing a disk with Windows. A name such as "hda5" signifies it is the first partition of an extended partition.