Well he can obtain another cd from a friend and reboot on it and do repair. Or he has to download from a link and burn and goes on. Or he can use a live linux cd
http://community.plus.net/blog/2008/...-the-easy-way/
In this case he has to remember a restor point where windows xp behave normally.
Bartpe 9.9 has also a minywindows xp on it. So he can boot on bartpe and choose mini windows xp and can run some chkdsk commands.