Sir go to "wordpress.org" and in the "Plugins" tab search for "counters". You might find what you're looking for in there. That's where I get my plugins for WordPress.
I hope this helps.
I'm just new here so correct me if I'm wrong.
IMHO to block the user, simply go to your "Profile" and add that person to your "Blocked Forum Users" list. It is located at the bottom part before the "Save Changes" button.
I hope this helps.
I use ESET Smart Security now but before when WinXP is still in use I used AVG and MS Security Essentials. And, yes knowing what sites to avoid and what not to click is still the best remedy for viruses, trojans, worms and the like.