It's probably broken
no. if your ipod doesnt work then you trade it into the apple store for the exact same thing you had.
To unlock the iPod Nano you simply enter the four digit number the owner set when it was first locked by using the Previous / Next / Select buttons. And if you have internet you can download itunes and then connect your ipod nano to it on not off and it should work.
yes
yes
yes
Ipod nano 6 gen does not have a built in speaker only nano 5 does
yes it does and it is called an ipod classic. it is just fatter and exactly he same
no
no, they will only work with the nano, as the nano is quite a bit smaller than other ipods and mp3 players. If you bought a speaker for an ipod touch, it would also work with the nano.
It may be because your Ipod won't play movies. I have an Ipod nano, and it doesnt play movies. And if that isn't the problem, I would try buying a MP3, they are cheaper and some can play movies.
No. go to "ipod games under itunes