If the pups are having accidents in their crates it probably means the crates are too big. They should only be allowed to stand up and turn around and lie down comfortably- if they have excess room they may reserve one end for going potty and the other end for sleeping. I would recommend partitioning off part of the crate so they don't have accidents in there.
Also, I've never used puppy pads, but I think it would probably be a better idea to get the dogs used to going outside right away- that way they know that it's only ok to go potty outdoors and it might be less confusing in the long run for them.
Good luck with your puppies- goodness knows that one is hard enough!