As an avid Mac user, I was faced with one of the worst things that could happen: I had to give up my MacBook Pro. Granted, it was never mine to begin with. I was using it to finish a movie score and after the score was finished, I had to relenquish the laptop. The producer, however, chose to thank me by giving me an entry-level Acer, thinking this would be an acceptable substitute. I'd heard all the scare stories of having to buy high-priced anti-virus software, and was determined to make the Acer useful and as worry-free as possible for me.

That meant getting anti-virus software. On the Mac, I'd...