#1) I strongly advise you not to load all of those iamges on to the hard disk drive of your MBP unless you have a second HDD or better yet an SSD installed for just your OS and applications. You will appreciably slow down your compute. See
http://eshop.macsales.com/shop/internal_storage/SSD/Mercury_Electra_3G_Solid_State for details on installing an SSD. If installing an SSd doesn't appeal to you, get an external HDD, possibly one that is portable to store the images on.
#2) It just takes time and patience.