Aww, my old pocket pc, it forever will have a place in my heart.
The bad news...It sounds like (Somehow) Your battery died, and that model pocket pc doesn't have a backup battery (Pretty sure) Which means your dad is gone. There's no way to recover lost data from volatile memory.
I'm sorry, I know your pain. May I recommend
SpriteBackup For a great Pocket PC backup solution I personally use and love.