Download and set Diskeper09 to run in the automatic mode and let it finish the job. It defrags even under low free space and extreme fragmentation with ease. Best defragger out there. Here is the free 30 day trial http://www.diskeeper.com/defrag.aspx
Tell him how long the defrag took. I just defraged an NTFS drive under XP that hadn't been done for a year at least and it took about 10 minutes.
If he checks in device manager under IDE he may find it's not running under UDMA but dropped down to some very slow compatibility mode. They do this if they have errors and you don't realise unless you know where to look.