Is it possible to use a XBee module to controll a quadcopter?
Depends on many usage factors:


Indoor or Outdoor?
How far from the computer will it travel?
Will it merely be receiving commands from the PC? Or will it have complete control over the copter at all times?
Are you trying to transmit a lot of data to/from the copter? For example, and onboard camera?


Xbee can be great for many applications, but it can lose signal integrity pretty quickly in indoor applications (sorry don't have much experience outdoors but it should be a big improvement). The 100m indoor specification is more of a pipe dream in my experience. If your PC is acting more like a brain than a command center for this quadrocopter you could run into trouble very quickly. 

Personally I would have a decent embedded system onboard the quadrocopter that can make good decisions on its own and maybe only report back sensor data when it's needed. Having the PC make time critical control decisions like balancing the thrust from the motors will be a nightmare because of latency and signal integrity. Instead you could, for example, have the computer tell the copter "go left for .5s" and it will know how to execute that command. 

I wouldn't bother trying to use a camera onboard with XBee unless all the computer vision processing is done on board the copter.