first of all, you do not want to set up a router as a Hub
that has nothing to do with this... FYI.
here's a few instruction on sharing a file
To share a drive or folder on the network
Open Windows Explorer, and then locate the drive or folder you want to share.
Right-click the drive or folder, and then click Sharing and Security.
If you are sharing a drive, on the Sharing tab, click If you understand the risk but still want to share the root of the drive, click here.
If you are sharing a folder, go to the next step.
Do one of the following:
If the Share this folder on the network check box is available, select the check box.
If the Share this folder on the network check box is not available, this computer is not on a network. If you would like to set up a home or small office network, click the Network Setup Wizard link and follow the instructions to turn on file sharing. Once file sharing is enabled, begin this procedure again.
Notes
To open Windows Explorer, click Start, point to Programs, point to Accessories, and then click Windows Explorer.
When you share a drive or folder, anyone who has user access to the network can read the contents of that drive or folder. If you want to remove the drive or folder from the network, follow steps 1 and 2 above to get to the Sharing tab. On the Sharing tab, in Network sharing and security, clear the Share this folder on the network check box.
To allow complete access to the contents of your shared drive or folder, follow steps 1 and 2 above to get to the Sharing tab. On the Sharing tab, in Network sharing and security, select the Allow network users to change my files check box.
To change the name of your folder on the network, in the Share name text box, type a new name for your folder. This will not change the name of the folder on your computer.
If you are logged on as a guest (a guest account provides access to the computer for any user who does not have a user account on the computer), you cannot create a shared folder.
The Sharing option is not available for the Documents and Settings, Program Files, and WINDOWS system folders. In addition, you cannot share folders in other user's profiles.
if you want to see all files, everything you will share the c:\ drive however i would not recomend that.
To open a shared folder on another computer
Open My Computer.
Under Other Places, click My Network Places. The shared folders on your network are displayed. If they are not listed, do the following:
Double-click the computer where the shared folder is located.
Double-click the folder you want to open.
Note
To open My Computer, double-click the My Computer icon on the desktop.
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