Here is a picture of my hdd's partition table :

I wish to install Ubuntu in the free space shown in the below picture. However I don't understand how to configure the installation. I chose the something else option at the installation menu, after which the installation type window was displayed. I selected the free space and pressed the + button beside the Change.... Then a window popped up :

I want to use the entire space for my ubuntu installation hence didn't make any changes in the size. Didn't understand the Use as: drop down so I let that be. The only change I made was selecting \ in the mount point. Then clicked OK and Install. Then this box popped up :
I didn't understand what to do next, so I quit. Please tell me what options I need to select to install Ubuntu in that 100Gb(93.14Gb) of free space. Thanks!