get a controller to USB and plug in a USB thumb drive to the xbox. it should detect it and format it to XBOX file format. download the Action replay software and edit the settings file in notepad, change the USB device to match the USB device that the thumb drive matches with. Then you should be able to move game saves onto it (via action replay) and from the USB onto the xbox.
Yes FTP is the way to go if there are a lot of files to transfer. But it is a pain to set up if you're not going to using it regularly.