Creative Gigaworks: config + mounting questions...

[Richdog]

Hi gents, I just picked up a set of Gigaworks S750 for my bedroom and have two quesitons:

1. Can they be theoretically used as a 5.1 system (ie: don't connect the two back speakers)
2. Is ceiling mounting speakers a good or a bad thing sound-wise?

Reason for the first question is that I may not want to hook up all 7y speakers right away and am just wondering if they can be used as a pure 5.1 system just by not connecting the bavk speakers. And for the second question i'm looking at ceiling mounting to keep all the wires out the way, and could route them through the loft with little trouble. I'm just wondering if it could prove to be any sort of negative thing from a sound quality/experience perspective.

Thanks in advance.