@snapzzz3
Having a Backup (BU) is not an option or a luxury, but a necessity. Why? Because all HDs fail, some on first start-up, some after 5 years of sturdy use. External Hard Drives (EHDs) are incredibly cheap in comparison to a computer (and especially in comparison to the fees of a professional data recovery service).
If nothing on your Mac is worth saving, then one doesn't need a computer at all. After all, one of the central planks upon which computers are founded is storage — and particularly storage of precious, confidential or otherwise vital files.
So before you consider formatting or using your Snow Leopard Discs, buy an EHD, preferably with a storage capacity 1.5 to 2 times that of your Mac's HD. Use Time Machine and this will backup your entire system, files, settings, the lot. At the very least, BU all your photos, music, precious files to the EHD.
No one knows what will happen when you try Snow Leopard. Could be great, could be catastrophe. What we do know is that formatting deletes everything. BU please.
Ian