Stories by: Christopher Null

Users looking for a free antimalware product to protect themselves have long enjoyed Avira, which is available in a no-cost version for personal use, but which subjects you to a single daily pop-up urging you to buy the full suite.

The word "essential" denotes something of absolute necessity—something that you can't get by without. But Webroot Internet Security Essentials 2011 ($89.95 for one year, three PCs, as of 12/2/2010) is sadly a bit of a misnomer: Its antimalware performance proved it was simply not up to the task of securing a modern PC. If you want "essential" protection, you'll need to look elsewhere.

Let's start with the good news: Panda Internet Security 2011 ($81.99 for one year, one PC; $91.99 for one year, three PCs, as of 12/2/2010) has some of the best protection going. Its and 99.8 percent detection of samples of known malware was tops among the 13 applications we tested. It completely blocked 21 of 25 attacks in real-world malware blocking tests (that help determine how well it can block brand new malware), and partially blocked three more, which, while not a top score, is still a solid performance. It's also no slouch in fixing downed machines, removing 80 percent of active malware components.

Novices will want to run, not walk, away from G-Data Internet Security 2011 ($45.10 for one year, one PC; $63.25 for one year, three PCs, as of 12/2/2010). While it's more than capable at stopping viruses, its complexity, cluttered interface, and overly scary warnings make it less appropriate for more casual users.

The good news is that Comodo Internet Security Complete 2011 ($69.99 for one year and three PCs, as of 12/2/2010) blocked a full 25 out of 25 of real-world attacks in our hands-on testing of the product.

Simple, simple, simple. That's the marching order of F-Secure Internet Security 2011 ($119 for one year, three PCs, as of 12/2/2010), an antimalware utility that focuses on safeguarding the computers of novices and especially families.

Are you a casual computer user who wants a streamlined security software experience? Or are you a dyed-in-the-wool computer pro who wants access to every configuration option, security alert, and log- file entry?

Does slow and steady win the race? PC Tools' answer to this question is a definite yes: Get it clean, no matter how long it takes.

Bargain hunters: Be patient and you'll often find McAfee on sale at a deep discount: The company's Internet Security 2011 (regularly $74.96 for one year, three PCs as of 12/2/2010) is often available for as little as $50, making it by far the cheapest way to secure the PCs you have at home.

Figuring out what's wrong with a balky computer takes a bit of detective work -- but with our advice, you can solve the mystery in no time at all.