Setting up home network using NETGEAR WGR614

I have the NETGEAR WGR614 setup and it is hard wired to one of our home computers which also has the printer connected to it. The other two computers (Dell Inspiron 600m laptop and a Dell desktop) can connect to the internet thru the NETGEAR as well.

 

How can these three computers connect to each other? (Pretend I know nothing about networking) I'd like to be able to access files from one computer to another. I'd also like to be able to print from any of the three computers to the printer that's connected to the hardwired computer.