Hi Pat! You are running a very small system, by today's standards. However, why RDF is baulking at #2001 sounds as though it (RDF) has a set limit for records. If your system was "bogging" down, I can't see it refusing to work at a "nice round figure" - it would stop when it felt like it :-). Unfortunately, I don't have anywhere near that amount of records in my RDF to test it for you.
Do you have anyone in the family with a larger (RAM, processor and harddrive) computer that you could run your RDF files on? You would need to install PAF 2.31 on their computer and copy your RDF files over to there, named exactly as they are now. Then see if you can enter #2001. As I said, I cannot see any reference to a limit on the database in the PAF 2.31 Manual. That of course, does not mean that there isn't one.
Let me know if you are able to trial it on another computer, wont you?