since you will be connecting the subwoofer to the "subwoofer pre-out" on the receiver, you will need an RCA to RCA audio cable. If it is a short run to the sub, you can use one cable in the typical red/white stereo audio cable. If it is a run longer than 6', I recommend a digital audio coaxial cable. It's still RCA to RCA plugs, but the cable itself is RG59 coaxial cable.
http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10236&cs_id=1023601&p_id=620&seq=1&format=2
Of your speaker choices, I would lean towards the 3 speaker set LCR3-P
It is a little strange, but you could save a few bucks getting 3 RC1 speakers separately, but I'm not sure which of the two options qualifies for the 20% off sale right now, maybe both.