Ok I have to check iTunes. Everytime I use that thing it seems real clunky. Maybe I got old guy syndrome.
It is quite easy to do from within iTunes, though not as intuitive as maybe it should be (or maybe there's a way I don't know about). Anyway, here's how you do it:
In iTunes preferences, with the General tab selected, there is a button lower down in that window that says Import Settings, click on that.
Then, choose whatever settings you would like to convert to (MP3 256kbps or whatever). Then accept the new settings and go back to your music library. Now, select any/all of the music you want to convert (you can do it one song at a time, or select multiple items by holding down the shift or command keys while selecting stuff). Once you have selected the music you want to convert, either right click one of the selected items, or pull down the Advanced menu, and in either case there should be an option that says something like "Create MP3 version" (this option will vary depending on what you set your import settings to).
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