One thing I would suggest IG is that once you upgrade, install Admin Tools.
Here is one suggestion
http://www.opensource-excellence.com/ose-anti-hacker.html There are some similar free extensions as well.
I use ksecure and jHackGuard, both have free versions.
They also do a fairly good job.
Spam is much easier to stop than hackers, but I suggest that you take both precautions.
For spam there is also SpambotCheck. You can use some of the spam programs together. Depending on your site configuration.
If having more than one gives you n issue, I would simply disable them and try one at a time to see which works best for you.
There are indeed several extensions to deal with spam and most work rather well.
Now if they would just find a way to deal with spoofing I would be happy..LOL
I visited your forum.. Very nice forum with lots of info.
I have never visited England, but one day I would love to visit some of the castles there.