I take from your story that each computer can ping the other computer. That's good.
Now, create a share in windows and make sure that the firewall accepts file & printer sharing connections. Then, using konqueror type smb://firstname.lastname@example.org.??/ in the addressbar.
Then you should be able to access the shared folder.
For internetconnectivity, you can set Windows to act as a router. I believe you have to make a "network bridge".
Good luck and tell me if it worked..