How do I easily add surround to my 2 channel setup

Well first things first. My current system is:
iMac Lossless iTunes Music Collection >> Lossless to Airport Express >> toslink >> X-DACv3 >> Old Junky Integra reciever >> Totem Acoustic Sttaf's

I have been waiting to aquire a Jolida 302b to put in place of the old Integra to give tubes a try ...I am not dead set on this though ...i picked it based on review and price point (can't audition it here in Indianapolis).

My dilema is that we have decided to buy a condo and it allready has 2 in-wall and 2 in-ceiling wired speaker cavities in the main room, and 2 additional installed in-walls in the bedroom (all wiried to one jack behind drywall). I don't care a great deal about having a super surround system, but since there are there ...why not use the speakers. I watch a few movies and a lot of sports, but mainly listen to music. (maybe 25%/75% movies+sports to music). I would probably just do a 5.0 surround setup and use the totems for my L/R and ceilings as surrounds and maybe the 2 in-walls as center? (they are about 4 feet apart ...so

I am thinking of getting something like a Marantz SR5600. It is 90 Watts (my totems have a sensitivity of 88) and it has Pre-outs for each channel ...this way mayby I could just get a dedicated AMP? for the Left/Right. I dont want to spend a ton of money here (less than 1G) and I could sacrafice the x-Dac if the reciever had toslink and a decent Dac (maybe use that money for a dedicated amp for the front channels?). Also if there is an integrated surround that performs well in stereo I am open to suggestions.

Budget ~$1000 if I keep my Xdac ...~$2000 if I sell the x-dac and use the receivers.

I listend to Jazz, Americana and watch sports and movies.