Grey = the disk
Green = primary partitions
Pink = logical partitions inside an extended
White= usable free space or unusable space
My drawing could certainly be better but it is a good description of your situation. In the end your partition layout is fine and there is nothing wrong with it. The Drakex program first created a new extended partition. A extended partition. is a special partition used to get around the limit of 4 primary partitions. So a extended partition holds other partitions.

Guides on partitioning can be found on google. I found this one. http://www.pcguide.com/ref/hdd/file/...titions-c.html