Ok what u need to do is in the moving van DON'T get out.in gameshark put in the master code (9266FA6C97BD905B5ED35F81B76A68E5FAB1) and the warp to battle frontier code (19C67C65668994318B106757.) now walk out of the van while holding L. u will meet mr scott. anyway go to the battle frontier tower.go to the first scientist guy (on the left) and talk to him. register for a single battle and let him save the data. choose any 3 pokemon and while ur walking thro the door hold L.now in gameshark put in these codes: (AE44960EADD670C560A026F8AE44960EADD670A4A310E655) and (49C6BF4EE2DBD9449F0766D1) now press select and A. choose your home town (littleroot) and go inside ur house. go back out. and so on and so on.
NOTE: only for emerald not any other game.
NOTE 2: if u got confused watch this youtube: http://www.youtube.com/watchv=NRLjQ70Bieg&feature=fvw