loading probs...

every few roms i d/l it will have probs loading: harvest moon island happiness, megaman ZerkerxNinja, new ultra kirby game, and Disgaea + couple others
all of them loaded halfway on my ttds and then black screen shows saying error.
ive read through forums and ppls says to backup and reformat so how do i do that?thx...

That's usually for freezing problems. Update your firmware by going to http://www.linfoxdomain.com/ds/.