Thats easy... grab hold of the manual and see if you have the backup/restore program in the software build. IF so backup to the SD card and your done. full restore takes about 3 minutes and will make the machine look like it never went flat (well the time will be off)
if you dont have it the proggie is available for free from microsnot if you have a registered windows Mobile OS and will run straight from the card so if you loose the main one due to the batts being flat you can still do the restore from the mem card.

