I've got some Idiot that keeps registering on my site, and then posts crap about George Bush.

The email address is always the same. How can I ban this idiot?

Read this rather lengthy thread

You can ban registrations with specified email addresses. I would change your registration settings to require administrator approval for a while, if it is not already

I have these idiots on my site from time to time to...
I simply figured out the true ip he/she came from from the access logs and denied those ip ranges

The user masks his ip, by using one ip, the true, to set up the comment post, then using fake ones to post with...
My site isnt to busy so its easy to spot the pattern in the logs

I havent tried the security suite, but I might do that in the near future, I assume that will at least see that the same session id uses the same ip during the session.