What is your current system? That will affect the answer. Do you have a full AVR and speaker set? Or a one-box thing?
Whatever you do, you will never make the surrounds and sub fully wireless. The speakers still need to be powered somehow.
You can get systems where you put a wireless transmitter on the L&R surround pre-outs of your main AVR. You then have a secondary amplifier at the back of the room with a wireless receiver attached. This drives the surrounds. This approach requires an AVR with pre-outs though.
So I really need to know what system you're trying to add this to.
Unless you start spending fairly serious money, then quality will be degraded by going wireless.
By far the best/easiest option would be to find a way to run cables. Around the edge of the carpet, or in D-line trunking maybe?