I have gone into all programs, accessories, system tools, backup I have selected the backup wizard advanced option and clicked next.

Which of the 3 options should I select if I am backing up in preparation for a clean install?

Backup everything on this computer,
Backup selected files drives or network data and
Only backup the system state data

Which of those 3 options should I select in preparation for a clean install of windows XP
My pictures, music and videos are my main concern.