Here is another reason to get the FS51's, $20 more off.
Newegg.com - Pioneer SP-FS51-LR Floorstanding Speakers Pair
You don't need stands, the FS51's are towers, speaker cables you do need:
HDMI Cable, Home Theater Accessories, HDMI Products, Cables, Adapters, Video/Audio Switch, Networking, USB, Firewire, Printer Toner, and more!
you can get all your cables here and I would use bare wire connection on the speaker end and banana plugs on the receiver, or for convenience banana's all around. If you can't raise the 51's sit lower to keep tweets at ear level.
You can get the matching sub, I can't attest to how good it is, but for the price right now you can't go wrong.
Newegg.com - Pioneer SW-8 100W Powered Subwoofer Each
It will get you buy at that price until you can upgrade to better sub. With the 51's you may feel that you don't need a sub at this point.
As far as sound card/DAC, I'll let others chime in here, I still can't see why you would want these.
You could get this if you ever want to expand your setup and it has an optical digital input (DAC)
and much better speaker binding posts than the Sherwood which I just noticed has spring clip terminals.
DENON AVR-1312 5.1 Channel A/V Home Theater Receiver | Accessories4less
Hope this helps or did I just confuse you more.
Cheers Jeff