So I've been toying around with my Nikon D3000 and I'm having a problem figuring out how to get this thing to take crisp pictures of moving objects (mainly dogs). I've messed around in S-mode with no luck (all the pictures come out either too dark or too grainy) and the "sports" mode still leaves pictures looking blurred. What settings do you guys use to capture your sibe's in motion? I've tried to do some research but haven't found much - read something about adjusting ISO sensitivity, but I have no idea what to adjust it to. o___O

Any advice would be greatly appreciated!