Start looking at the manuals as they pretty much answer all of your questions. As for a camera, depends on what you mean by hooking it up. I'd just get started with getting a robot to roll forward and detect object before thinking about cameras and other things.
You will be programming the robots, ie wrtiting your own code. It'll help to look at code that other people have posted to save you time and also to learn.
check the manual for how to connect it to a pc. You'll be using either usb or serial(oldschool) .
Click on the "Data Sheet" link for manuals but here is the link that I found:
Please change the title of this to something like "Which motherboard (basic stamp?) to choose".
("hello! i need some help!" is a really bad title for anyone trying to navigate the site and find information)