I Dont know how to insert music into my player

when I go to MY COMPUTER, i click on the sansa c250 pic...
after that i get the screen that has a folder named SYSTEM, VERSION.SDK, and a notepad named VERSION...I click on the SYSTEM folder because I cant put Mp3s into the other ones...
Then A screen comes up with 3 folders - DATA, MTPCONTENT,WMDRMPD -

+( DATA - all PDB files - ALBUM, ALBUMART, ARTIST, GENRE, OBJECT, and REFS)
+( MTPCONTENT - FOLDER "0" - FOLDER "0" - folders 0-9 and "A" - all of which has media pler content some music and some i cannot play)
+( WMDRMPD - STORE.HDS)

I tried putting my files into the MTPCONTENT - 0 - 0 - folders 0-9 and "A" none of which even showed up on my sansa... I havent tried putting them into the other folders but i highly doubt that its going to work...im starting to think if theres a program to open the PDB files and then inserting the music there...
WELL.... i cant do anything now because ive got to go to sleep and then comes church tomorrow... if anyone can help i'd appreciated it!!!! thx!!!
oh and if u want to contact me - infernofirepower@yahoo.com
thx a lot!