rl168,
Some receivers have a multichannel stereo setting, which is basically the front R/L speakers, and the Back R/L speakers will have the same signal going to them. Some have Dolby or DTS matrixing which can take a stereo signal and interpret it, and then send it to all of the speakers in a way that mimics surround sound. At least that is how I understand it. I am sure you can get a much better explanation from some of the more experienced members of this forum.
Now, when you say you have 4 "drops" in the living room, and one in the kitchen, what do you consider a drop? And how is it set up? Do you have speaker wire in the walls, going to wall plates, or bare wire hanging out? Or is it attached to the floor or wall in some way? Pictures may help if you can, or even a drawing. See what you can do.
Of course there are probably myriad ways to accomplish what you want to do. It is going to depend on the equipment you have available, and where the wires can go etc.
-capT