No you have reached the partition limit imposed by Windows for a single Hard Disk Drive.
It is possible to have ...
Four (4) Primary partitions or
Three (3) Primary partitions and a single Extended partition, inside the Extended partition there can be as many Logical drives as there are available drive letters.
You have an empty Primary partition on the right side which can be deleted and open up space for another Primary.
So you can use free Partition Wizard bootable CD to rightclick>Resize C to see how much more it will shrink by dragging its right grey border to the left.
Next you can delete the 11.77 gb empty partition on the far right side to open up another Primary partition, create a New NTFS Primary partition in the shrink space you made from C.
Either add the deleted 11.77gb to G by rightclick>resizing it into the space, or rightclick resize the Extended Logical, hold it with a left click to slide the whole thing over to the right into the deleted space.
You can then create a new Logical in the Extended partition on the left side in addition to the Primary (since you said you wanted two) or just use a Logical or Primary there. To create a new logical in the extended's left side, rightclick to Resize it and drag the left grey border to the left to make space for a new partition.
Partition Wizard : Use the Bootable CD
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