Convert iTunes library to mp3?

I have my reasons for this, and I am aware that, under most circumstances, mp3 is not the best option. But:
a) I need to copy my library to an mp3-only player, and
b) Roku only supports mp3

Is there an easier way to convert 4,500 songs than setting import to "mp3", highlighting every song, clicking "create mp3 version", and manually deleting all the originals?

Le Big Mac said:

If you proceeded this way, couldn't you then sort by type/encoding and do a batch delete?

Click to expand...

I hadn't thought of that. Thanks!
Also, "Jolly Giant", Thanks for the reply!