In Windows XP, it is possible to rename multiple files at the same time. To do so, follows these steps:

1. Manually select the files that you want to rename

2. Right click and select Rename

3. Type in the new name for the selected files.

If everything worked correctly the files should all have the same name, but be differentiated with a number in parenthesis, like this: newname ; newname (1) ; newname (2) ; etc.