First of all, what exactly do you mean when you say “Oracle database file” Do you really mean a Oracle table (like EMP, or DEPT), or are you talking about the database file in which Oracle stores its entire database?
You cannot read or write to an Oracle database file without an extreme amount of difficulty. It is a proprietary file format, with way too much intracacy involved for what you literally said in your question.
I’m actually pretty certain you meant an Oracle table within an Oracle database, not the database file itself. For this, you need to connect to the Oracle database running on that Windows 2003 machine, using a userid that has access to to the tables in question, when perform your data access using SQL.
Once you get yourself connected, you should then have access to the resources necessary to show you how data access/manipulation is done.