Without an xp cd I don't think you are going to be able to do anything. Easiest solution is to purchase a new xp systems disk and use that to effect a recovery as it would appear that the boot.ini file has become corrupt. Your friend should have either the Packard Bell recovery disks that came supplied with the machine or to use the recovery disks that should have been made when the machine is used from new.
The two links show where you can purchase operating systems from, they can be bought online. I know both stores well and both are reputable ahving been to both stores and having purchased online from them. Delivery is usualy the next day.
However if your friend can find his recovery disks then that would be by far the better solution.