Remote access to my office computer from my home computer.

I own a small mortgage company and we have 5 computers. These are NOT set up
in a network, per say, but are all connected to the internet via
cable(Comcast) and are split with a common router. We DO have a shared drive
setup, with one of the five computers acting as the shared drive host.

My question is "Can I set up a way to completely access my office computer
form my home office computer" They are both running windows XP-professional.
I tried to do the "Remote Desktop" as instructed by Microsoft, but it does
not work. Is it because our office computers are not set up as a true network?

Can anyone suggest a way for me to access my computer from home?

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