Okay, download EaseUS Home Edition, it works just like disk management but better. Do you have any data in the 31.48 GB HDD?
Install, open program, Go to Main Screen, and tell me what you see in your 31.48 GB. It may show unallocated space, "other," or other possibly other partitions. If not, we may be able to extend the primary partition. Let me know what you find first before doing anything.