Moved to Editors Hideaway as this is where this belongs. Please post in the applicable forums, and please follow rules and don't post in all caps.
You cannot rename players using DDT and EDT files.
To make a data update you will need to use a data editor (that operates on the pre-game database, *.dat files).
For this purpose you can use the official editor, which you will find conveniently located in the same folder as your FM05 executable (default: C

Program Files\Sports Interactive\Football Manager 2005\).
You can find further details and tips and hints on using the editor in the file fm_data_editor_guidelines.pdf located in the same folder.