OK to convert a WMA file to MP3 try this:
Go to:
Media >> Convert / Save...
Select your WMA file and press "Convert / Save". In the new window for the Profile select "MP3". Tick the "File" tickbox, press "Browse" and navigate to where you want to save your MP3 file. Enter the MP3 filename, including ".mp3" into the File name section. Press "Save" and "Save" again to start the conversion.
For example your Stream output window might look like this:
If you want to change the bitrate (default is 128kbps) enter it into the sout sting at the bottom of the window (e.g. change ab="128" to ab="192" for 192kbps).
For an iPod video do pretty much the same thing except select a video, the "iPod" profile, and use ".mp4" for the filename extension.
If you want a simple drag-and drop convertor look at e.g. something like
MediaCoder or some FFmpeg-based GUI/Frontend.
Arite.