Paradox 5 is an old sequential open file database that does not support any of the new functionality of modern SQL databases.
Also, Paradox 5 is a horrible database. It is constantly getting corrupted and needing reindexes and repairs. Plush it Blobs are just plain broken so don't try to use them. If I where you I would consider using Firebird instead of Paradox. It is a fully relational SQL database that does support transaction just like the industrial databases and it is Open Source. Plus there are many tools support by Delphi that will work with it, including the BDE.
If you got the money then I recommend MS-SQL Server.
Granted you will need to learn a little about ADO and ODBC instead of that dead BDE which no one uses any more. Firebird also support ADO and if you start using ADO instead of the BDE you will be able to make code that works on a multitude of databases.
Just MHO based on personal experience with Paradox and Delphi. Take it with a grain of salt.
To be honest, I stop working with Paradox back in 2003. At the time there were some datapumps that would move the data over for you but they did not work the way I would like so I just made my own convertor that would open a connection to both databases and just move the data.
The new ones are probably better than the old Informix ones I had to use back then. Try this...