Backup has already been done. Whatever is left on the PC is not important, if there is anything left. I will try what you've suggested.
Ok, then yeah just use something like Rufus to create a bootable flash drive from GParted, and then boot off of it. It'll load your drive in a nice GUI, then you can delete specific or all partitions, and then create new partition and then format it to NTFS. AFter you "perform" the operations, you'll have to actually click the Apply button to perform the tasks that you queued up.