Depends on how your original system was set up. id it come with original Windows installation disks? Di it come with a set of recovery disks? Or did it, as as most common nowadays come with a recovery partition on the hard drive from which you are required to burn your own set of recovery disks. If your situation is this last one and you have not created the recovery disks you should do so as a matter priority.
I do not have any installation disks, i made a repair disk because orginaly i could not get into the OS or even into safe mode i couldnt do much. after i got it up and running i tried making a system recovery image but right before it gets done it says failed because of the hard drive but when i open up the external hard drive where i stored the image it shows it there. theres no recovery partition either.