Since you can see all the machines on the network map, then you should be able to go to Control Panel - Network and Sharing Center - and make sure your file and printer sharing are both turned on. Then make sure both firewalls on both machines are set to allow LAN access.
DON'T do Public sharing over wireless, unless you've secured your wireless connection (encryption or a MAC address access list) and even then, I'd think twice. Both machines will need to have the same user account names on them to allow for secure access to your folders (meaning if you have an account named Bob on one machine, the other one must have the same name, and Bob must be allowed to have access to that network resource. )
Um, you might try
www.practicallynetworked.com and scroll down to the Forum link (in the blue bar on the left,) there should still be a Howto stickied in the forum that walks you through it step-by-step.