Accessing sharing folders anywhere.?

I am using windows xp in both of the machines at home and at work. How can I create a sharing folder at home and then access it from my office?
Note: I am not a tech guy so pls explain point by point if possible.
Thanks in advance...

Thanks for the message.
* I am using Win XP Pro in both machines
* No firewalls except from windows' own which I can disable if required.
* I have a wireless router at home.
* No modem. I am using wireless internet connection from the same ISP both at home and work. (they have a receiver on the roof and a network cable plugs directly into the switch at work. At home, the only difference is the network cable is directly plugged into the wireless router (Zoom Wireless-G 4400 AP+2)

You can use remote desktop the only problem there is if you have dynamic address then you need someone to configure your router, to assign static address IP address to the computer that your going to access at home.

You can use goto my PC, It has 30 day trial period. Very simple to use, very intuitive when installing it at home they will tell you step by step on how you can access your pc at home. See if you like it, if not then you can use other methods.

there are several ways.
the first way is setting up a VPN server at home, which might be complex for you.

the second option would be setting up a remote access. that can only be done if you have XP pro at home.

gives us more details about the setup you have at home,

such as operating system "XP home or pro"
firwalls?
routers?
connection type and modem?