YOur best bet is just to use a Maxstream Zigbee for controlling the robot and sending data back and forth. The video/audio will get VERY expensive if you try and do it digital- buy a wireless security camera w/e microphone and use that instead.
You will have a separate TV monitor to view your robot and a PC to control it, but it will cost much much less and be much much easier than trying to get it all on a PC (that is, unless you get one of those webcams with WiFi built-in cameras, then it could all be on your PC.
THe hardest part for a beginner of what I Just mentioned is actually getting the Maxstream Zigbee to be able to control the robot (which means setting up circuits on the robot so that the Zigbee can control the motors and other things, which like others said, may be too much for a beginner.) THat said, if all you really want is a remote control platform with a camera (which is what it sounds like), then find a motor controller that has RS-232 so it can be controlled by the Zigbee and learn how to set it up. Everything after that is just mechanics and sticking those cameras and microphones on the base.