That's right I finally bit the bullit and upgraded this baby to WordPress 2.04. I stayed away from the 2 release at first, just to let it get smoothed out and then just got lazy. It didn't take ten minutes, the upgrade instructions on the site being slightly overkill, mainly backing up everything, but better safe than sorry.
The best thing to come out of this is I'm now using the Akismet spam blocking plugin and have been very impressed with it. Since activating it on Sunday afternoon, it's captured 160 spam comments, and successfully let the 5 genuine comments through.