MP3 player songs
 

I purchased a 20g dell mp3 player and it says it can hold up to 9900 songs or so. Im just wondering how to get the most songs onto it since right now its maxed out at 4500. I know i need to change all the songs to mp3 format and change the quality of the songs to make them smaller. But im not sure what the best setting are to get the max out of it.