Instructions
Go to "My Xbox" on the Dashboard and scroll over to "System Settings." Choose this option.
Select "Memory" from the list of option on the next page. This will call up a screen that shows what storage devices you have attached to the Xbox 360. Pick one of these to see the list of files.
View the list of game files. It includes such categories as "Games," Gamer Profiles," "Demos," "Videos," "Gamer Pictures," "System Items" and "Music." Select a category to view the files within.
Pick a file to see more information about it, including the device it's located on, file size and the day and time of its creation. From this screen you can choose to "Copy," "Move or "Delete" the file. The "Copy" option will make another copy on a different storage device if you have at least two attached to the Xbox 360. "Move" will transfer the file to another storage device. "Delete" will permanently remove the file from the storage device.