I'd move those KG-2's to the rear and get maybe some KG-4's for the front and a KV-3 for the center. Get a KSW-12 instead of the 10 and finding a receiver with just 5.1 and DTS is easy nowadays. I think you can get all of it for under $1k with some bargain hunting. Only problem is that Circuit City, Best Buy and Crutchfield don't sell Klipsch, and the Classic line (which you have) isn't made anymore (unless I'm mistaken), so you'll have to stick to eBay, audiogon, etc...
Good luck!