Hardware and performance

Thank you both for your responses to my question. Unfortunately, in my shared hosting enviroment I didn't have a lot of ability to put your suggestions to use. I decided to move our moodle installation to a co-located server we have all to ourselves, and miraculously the problems seem to have all gone away.

Makes me think that my hosts "rarely any load on the server" statement was perhaps incorrect and that it was indeed a function of the many sites competing for resources on his shared server.