Is there a virus scan for MacBooks?

Question

I was using "let me watch this" to watch survivor. I fell asleep, and when I woke up, there was an error message on my laptop, telling me I must restart my computer by holding down the power button, because my laptop was frozen. This message was in English, French, and Japanese. I'm afraid it is a virus, I could not even send the details to apple. Is there a affordable, trustworthy virus scan available for MacBooks?

Answer 1

My original post asked about a virus scan, an as you know viruses are self replicated, not downloaded.
That statement reveals a severe lack of understanding of malware, which is highly dangerous.  Most malware these days is NOT self-replicating.  Most malware comes as trojan horses, which rely on social engineering to trick users into installing them.  If you believe viruses are "not downloaded," you are at extreme risk of becoming infected.  You would do well to read my Mac Malware Guide.
I never said I was downloading, or installing anything, I was merely watching a video.
Many people have been "just watching videos" and gotten infected with malware as a result.  Consider, for example, the RSPlug malware, which has appeared on many less-reputable video sharing sites as a "plug-in" required to view the videos.
Further, there is currently malware out there capable of infecting a Mac with no user interaction needed, through vulnerabilities in outdated versions of Java.  (See Flashback using Java vulnerabilities and Flashback infections becoming widespread.)  As you indicate that you are using Mac OS X 10.5.8, you are running an outdated version of Java, so if you have Java turned on in your browser, merely visiting the wrong site could infect you.
(Note that my pages contain links to other pages that promote my services, and this should not be taken as an endorsement of my services by Apple.)