I have about 10 gigs of MP3s on my 40 gig iPOD which I want to upload to my laptop. I know that you need to show hidden files to access the iPOD but can someone guide me through this process please? After that I want to transfer data from my laptop to my home computer and would like to use the iPOD as an external HDD. The data is about 15 gigs. How do I do this? Can the data and the MP3s co-exist on the iPOD?