It is very convenient in winxp system, and the method is as follows:

1. Put the files you want to name in the same folder.

2. Select all files to be named.

3. Right-click the file to be named "1" and select Rename.

4. Just fill in the name you want.

If it's in win98 or 2000, you need to use other software. There are many such softwares on the Internet, among which ACDSee has this function!