hmm... d ko pa na-try yan. wala naman me another Ipod pa hehehe

1:1 kasi ang Itunes:Ipod. if you accidentally synced your Ipod to another PC with an Itunes library deleted lahat ng laman ng Ipod mo. (accdg. to manual)

I can think of only 1 way to do what you want:

in windows xp, create a new user account for your ipod nano, and another user account for your ipod video. playlists in Itunes are saved on My Documents\My Music of each user account.