WINDOWS XP RE-INSTALL ERROR HELP!?

In your case I would have to say FACE the MUSIC! If you had privileges on the PC and you were my kid, I'd say since you cant get on here and be responsible, you let friends on the PC, you mess with files you shouldnt, you simply no longer are allowed to use it period. Yes it can be fixed and NO you cant fix it because its way over your head. End of story.