If you are booting from the usb, and using the live image to check gparted, why isn't your usb visible in gparted? What size is your usb, out of curiosity? If the 1tb drive is the internal, please delete both partitions, the efi partition may be effecting your installation. Create an ntfs partition (or any other file system you don't plan on using) and format the entire drive. Then delete that partition, create a 500mb fat32, and your partitions for how you plan to install zorin (with seperate /home partition or all together) formatting as ext4. Then boot the live cd and attempt the install from within the live image using something else method. Choose the 500mb partition for grub (last choice after defining root /, and home /home partitions).
The only other thing i can think is that your drive may be on its way out. Changes after a long period of time sometimes bring to light bad sectors or a failing drive. I hope that is not the case.
Edit: The dual partition wipe is to remove any reference to the existing efi partition and any remnants of windows left behind. You can eliminate this by doing a thorough format instead of quick, but it will take the better part of half an hour or more.
