When you first get your new Mac and turn it on, it will ask you if you would like to transfer content from another computer. Be sure to do that, since it is the easiest way to ensure music, photos, contacts, emails, and other documents on your old PC will be copied to your new Mac. You can copy information later but it's not as easy as it is when you first set up the Mac.
14+ GB is a lot of information to transfer so be sure to use a wired connection between the two. Transferring wirelessly will take the better part of a day even under ideal conditions, and could take much longer.
Viruses on your PC, if there are any, cannot harm your Mac.
Once copied from the PC, verify that all your music has been successfully imported into your iTunes Library. Sync your iPod to the PC one last time as a backup, and then sync it to the Mac. Syncing it to the Mac will erase the iPod first so you will want to ensure the Mac contains all your music.
Enjoy your new Mac!