Convert aac files to .mp3

My daughter received a Zen Stone mp3 player as a gift. I went into my “My Music” folder and put some music on the Zen Stone for her. I found out that some of my music is in the “aac” format and didn’t play on the Zen Stone. I found one answer on how to convert: do it in iTunes. After I set iTunes properly to convert files to mp3, I dragged a folder into iTunes. It converted the files to mp3 (hooray!) but now I have TWO files for each song I converted in my My Music folder: the aac file AND the mp3 file. And the only way to get rid of the extra mp3 file now, is to go into each music folder separately in My Music and delete it. Is there a way to drag the folder into iTunes and keep all of the files from that folder together so they don’t get dispersed all over the My Music folder?

Or is there a freeware converter so I can drag the folder into it and convert them all?

Does iTunes give an option where your file conversions will be stored? Create a folder and put them there when you convert rather than in My Music folder, you can delete from there, or keep them and convert to other formats as needed, or delete at later time…
I don’t use iTunes ,but you could give DaudioK, Super or MediaCoder a try for aac to MP3 and store in “your new MP3 folder” for example…
http://www.videohelp.com/tools/DAudioK