Hi Brian! Well your system should be able to cope with running PAF. I had a similar system with only 48 MB RAM and it coped. Admittedly I have only around 10,000 in my database though.
The errors seem to be pointing to your Sources, so while it is an error it is not a major catastrophe. See if you can "browse" through your Sources and spot anything untoward in there. It is hard to describe what to do from a distance, but I am sure you will recognize anything out of place.