you cant
There is no such thing as 'installing' an iPod Touch.
There was an update for the ipod touch about 7 months ago and it allowed you to change the background on your ipod and you can also change the lock screen
no
You can install free text messaging apps, but you have to pay for minutes to call people on the iPod Touch.
No, however the ipod touch 4g has two cameras on it
Add a background image to the iPod Touch via the Photos tab while the iPod is connected to iTunes. You can then select the image in the iPod's settings and set as wallpaper. (See links below)
No
Sometimes depends if the apps that you install have bugs
settings/wallpapers
safari should already be on your iPod touch. it is a default app that cannot be deleted.
You first have to download a torrent of the version of firmware you want, and then you can install it onto your iPod touch
You probably need to make a itunes account