For the speakers -- I'd probably get the Kef iQ1's for everything. It looks like it shares the most drivers aswith the iQ5 you bought.
Get the Onkyo 605/6 or 805/6 that have already been mentioned.
Get the SVS sub you can afford.
Placement -- ideal placement would be an equilateral triangle with the front l/r, the center would be just above or below your tv. As for your surrounds, it will depend on if you're going with a 7.1 or a 5.1 setup. You could go here and see what Dolby Labs recommends.
I'd suggest you give us a new sketch of just the room you want to put your equipment in with ALL of the furniture, windows, etc. And pictures would help a lot. We're liable to just be confused with what you've given us so far.
i have the iq5 now i need a better center i was looking at iq 2c 1q6c and for rears def tech bipolars also thinking of getting denon 3808 or onkyo pro or nr906 , or elite 03 sc 05 def techs for rears and for sub def techs bipolar for rears can someone suggest something pls