welcome to Android Forums, ammurdoch
your samsung came with a usb adapter that you use to plug into the wall outlet, you simply detach the usb part from it, and plug it into your pc, the drivers for it should begin installing automatically.
from there you can select mass storage mode(which will let you look inside the external sd card)
charge only
PC Mode (which allows you to transfer pics and other media, but you can also do that with mass storage mode
some of those options may be available, and there might be a few more. i hope this helps your question