OT: iPod to Mac Mini
If I remember correctly, iTunes does not allow you to copy songs back from an iOS device to a computer. If you purchased the songs on the iTunes store, you can transfer these purchases to the computer by selecting the device in iTunes, right click it and chose transfer purchases.
If you synchronized photos from a PC before to the iPod via iTunes, the iPod will not contain the original sized files. iTunes only copies smaller versions of the original files that are hosted on the computer.
I would advise to get the original iTunes folder and the original pictures from the computer they are currently hosted on.