I don't have any money and don't plan on spending any
The quickest and most reliable way to transfer the data would be to remove the drive from the system that you now have and attached it to his new system and let him recover the data that is important to him with SATA or IDE cables as might be required.
The fact of the matter is no matter how you do it 450 GB of data is going to take a while.
Yes you could network the two and move it although that would be much slower and slightly less reliable especially over a wireless connection.
It is a bit surprising to hear that someone with that much critical data has not used other means to back up and secure that data. I would have thought that he might have used one of the many free...