Do you mean, what does this command mean?
mount -t vfat says to mount a partition, and the filesystem type (t) is vfat. /dev/sda2 is the partition it is trying to mount, and ipod is what folder it's trying to mount it to.
you may want to go into /dev and see if there are any sda entries, or read your dmesg and see if it says anything about a usb connection / vfat / anything interesting to get pointed into the right direction..
the can't read superblock means it just can't read it. more than likely it just doesn't exist.