The ID3v1 / ID3v2 gives you the ability to rename your files based on the ID3 information. To do this, make sure you're in a directory that contains MP3 files.

One you have selected the MP3 files you would like to rename, enter your keywords in the New File Name box. To view / insert keywords, click on the Insert Keyword button. Once you do that, you will see a window like below:

Select which keywords you would like to use to rename your file

Example: <v2Artist> - <v2title>

NOTE: Be sure to Preview your changes before clicking Apply