Partion query

I just got a Dell OptiPlex 780 to tinker with and I see it has no back up partion. (only 360 GB HD ), I have created a small partition to store a system back up , I have another on an external HD too but id like one on my pc just for convenience really. If I get a crash in my OS can I restore from the partition or is that governed by my installed OS too. Basically is the partition separate from the windows workings or is the real back up partition different from a created one.

My computer shows two drives one is a small partion a few hundred mbs and the c drive.There is no other drive listed as the main c drive totals most of my HD space.The other two pc's I have both have a back up partion present so im guessing the previous owner deleted it because of the small HD. What I meant about the "real" back up was is the original partion designed for a back up somehow modified or is it just the same as a partion I can create by shrinking my main c drive.I know a disk failure would effect all partitions on the drive but I wanted a system back up handy on my pc in case of a windows problem that would be fixed by restoring the back up straight from my pc and which I could keep current and update my external back up less often such as after any major changes to my data / system. I am thinking of adding a second HD which I would place my back up on which would then be seperate from my c drive but at the moment I cant afford to do that, my external back up HD is only a 360GB drive so there is not much point putting that in the pc and im hoping to get a 500GB -1TB drive to install asap.