Changing HHD on Averatec 5500. I am trying to decide whether it is worth it to upgrade and change

Question

I am trying to decide whether it is worth it to upgrade and change my hard drive on my three year old Averatec 5500 or just get another computer. There is supposedly a slot for a hard drive upgrade (according to the info in the pathetic Averatec user manual) but no directions about how to back up and save the old c drive into and put it on the new upgrade. Do you know if this is done simply (like a RAM upgrade which is a no brainer) or requires some specific tools and software to complete the upgrade? Thanks for any help. Don