With XP from DOS he can't access C drive, so he will need some sort of disk space. But boot floppy is nice to get to that partition, now that OS is already installed. Partition magic should be able to resize partitions that already exists (don't ask me how to get this one
, it is on sale in best buy - usa - for about 20 bucks).
Use moslo (or whatever is called that program) to slow down your computer, if you have speed problems.