I'm not sure how to handle this

I subscribe to a traffic monitoring service. It's not because I'm paranoid, it's just because I enjoy seeing what sort of things lead people to my website. I can't say I'm happy about it. Apparently some idiot who spammed my site with advertisements for sites of a nature that I dare not mention keeps coming up.

Should I delete the comments all? I'm not sure that would help as the damage has been done and the site's been searched via Google's blog search that way. On the other hand, it has been directing quite a bit of traffic to this completely unrelated site. I just wish I could look at the list without worrying about who might be looking over my shoulder.