Yeah if you're looking for updated rosters and updated franchises for NFL 2K5, you can find the files you need at Operation Sports. You have two options for transferring those files. If you have an action replay, you can just copy the save files to the memory card. If you don't have an action replay, you'll need to connect your Xbox and your PC to the same network and transfer those files over.
https://youtu.be/DJOEen1-234?t=1633 Start this video at 27:13 if the time stamp doesn't work. It shows you how to connect your Xbox to your PC. You only need an ethernet cable.
You unzip the files from Operation Sports, then open up the folders, and copy the C975161D261D folder and the 0B9AB4D80B9B folder to E:\UDATA\53450030 on your Xbox. Then you can start NFL 2K5 and load the roster or the franchise.