When we move machine, copying the Oracle configuration is a problem. However there is solution for this problem.
Navigate to the following location,
Step 1: C:\Documents and Settings\ \Application Data\SQL Developer
Step 2: C:\Documents and Settings\ \Application Data\SQL Developer\systemXX.X.X.X.XX
Step 3: Copy the product-preferences.xml in the location below,
C:\Documents and Settings\ \Application Data\SQL Developer\systemXX.X.X.X.XX\o.sqldeveloper.XX.X.X.XX.XX
Step 4: Copy the connections.xml in the location below,
C:\Documents and Settings\ \Application Data\SQL Developer\systemXX.X.X.X.XX\o.jdeveloper.db.connection.XX.X.X.X.XX.XX.XX
Copy these 2 files(product-preferences.xml&connections.xml ) to your new machine in the same location