When it comes to proactive protection, Eset's NOD32 was the hands-down winner in "Virus Stoppers," our eight-program antivirus roundup. In our tests, it caught 79 percent of unknown malware samples when using one-month-old signature files. The next-closest program, BitDefender Antivirus 10, came in with a distant 61 percent.

NOD32's overall malware detection rate wasn't stellar, however. When pitted against AV-Test.org's nearly 900,000-strong "zoo" of Trojans, viruses, and other malware, NOD32 caught only 90 percent, compared to the 96 percent rate of top performers Kaspersky Anti-Virus 6, Symantec Norton AntiVirus 2007, and BitDefender Antivirus 10. It fared surprisingly poorly with 32-bit Windows viruses (approximately 1 in 11 samples in the zoo), catching only 73 percent.

In disinfection tests, NOD32 cleaned up all malware files but missed resulting changes to the Hosts network settings file and most of the less-important Registry changes, for a disappointing 55 percent success rate.