If you want to rename more then one file simultaneously then here is the application GPRename.
GPRename is a free application that allows Ubuntu users to easily batch rename, delete, insert, files and directories according to many criteria.
To install GPRename on Ubuntu, launch the Terminal and run this command:
- " sudo apt-get install gprename "
- tar xvjf gprename.tar.bz2
- cd gprename
- sudo make install