I want to format my new dell inspiron 7720 17R SE

Well, like several young people who are game-loving, I decided to get the Dell Inspiron 7720 17R SE which has great specs but there are a little bit of problems here to resolve.

First, when i look at the containing box and dell's website detailing the specifications of the laptop, it tells me that the machine has a hard drive capacity of 750 gigabytes. But when I check my laptops drive at the Bios at the start up, I still see 750 gigabyte. However, when I check the hard drive from the 'my computer'

window, I see 699 (which is 700 gig) instead of the 750gig. Can this be possible and if so, why?

Secondly, I want to format the machine and partition it according to my will. My greatest fear is that I will not get the preinstalled softwares with which the machine came with. For example, the cyberlink DVD player, the multimedia software which carries the name just MUSIC and is the default player of most supportive movies and songs. I hardly know if this particaular software comes with the windows 8 as I have windows 8 installed.

One of my greatest fear too is the Nvidia drivers or softwares that may be eroded away and can never be recovered given the poor network problems here in Ghana. I have the dell drivers CD but is the Nvidia one included in it?

Well, in a nut shell, I want to know why my hard drive is 700 even though it is supposed to be 750 gig. I also want to know how to recover all the pre-installed programs on the laptop after formatting. Plz I need great help before I start to format.