How do I get rid of 888-382-7416 pop-up error?

On my Mac mini I'm receiving a pop-up from http://www.rrld32-malware.com stating that "YOUR APPLE COMPUTER HAS BEEN BLOCKED" because of a registry failure of operating system error code: rundll32.exe and immediately call Apple at 1-888-382-7416. This seems like a scam to me and may be generated from a web page. Has anyone else seen this? How do I permanently make it go away?

Thanks!