Can you take songs off an ipod??? and how?

cuz i have an ipod and my dad put like 7000 songs on it and iwant 2 put my music on it but theres no room. and i dont have itunes so can i do it from windows media player so do i have 2 download itunes???. also i download songs form walmart and it says they not able 2 go on ipods or is there a way around that?? and how do you get rid of playlists??