You'll need to set up file sharing to view and exchange files. http://windows.microsoft.com/en-us/windows-vista/file-sharing-essentials Here is a video. http://www.youtube.com/watch?v=rP3eR3aNxEw
Windows 7 and 8 supports homegroups that might make your file sharing setup easier. http://www.addictivetips.com/windows-tips/simple-windows-7-file-sharing-step-by-step-procedure/
As far as Internet access goes,
Without getting too technical.
You need a device that can share your one Internet connection with multiple devices. Most commonly a simple wireless router is used. http://www.amazon.com/s/?_encoding=UTF8&linkCode=ur2&camp=1789&creative=390957&field-keywords=wireless%20router&url=search-alias%3Daps&sprefix=wireless%20ro%2Caps%2C490&tag=excharge-20
A router connects two separate networks and manages the traffic between them.
In most home network applications the router connects your local group of computers and devices known as the LAN with the Internet, commonly called the WAN or Wide Area Network.
If you don't have a router, another option is to set up Internet Connection Sharing (ICS). You can set up ICS on a PC with a Internet connection and connect it to another PC. This requires two network cards in the first PC. The Internet connection can be Ethernet or WiFi. http://windows.microsoft.com/en-us/windows-vista/using-ics-internet-connection-sharing. This method also requires the first PC to be active any time you need to access the Internet on the second PC.
Good Luck...