MS Security Essentials???? That is against my religion.
May I ask why? Just because MS is the company we all love to hate?
Yeah sort of. Everyone has their own reasons, I have mine.
Each person's particular reasons may differ, but they all rhyme.
Windows is the default OS for most people. We are stuck with it for one reason or another. Mainly because we have been brought up with (forced to use) it at school and/or work. It is hard to be delivered from Windows and MS Office especially once you are imprisoned. But we have a choice when it comes to the applications we use on a day to day basis. I avoid MS apps as much as I can. Besides Windows and occasionally Office and MS's patches, I don't install anything else MS. I would prefer to remove all trace of WMP, IE, Movie Maker, Windows Mail/Outlook Express or whatever it's called nowadays and all the rest of MS's slavery. It takes up useless space on my system. Some of these "features" can't be removed without problems since they are so tied to the OS and/or third party software is so tied to it. I support independent software writers, most of them freeware/opensource. Much more interesting and you can often contact the writer directly or on open forum.
For antivirus, I use avast!
which has always had a good reputation. New version has a much improved interface and uses less processes and memory. Tried about a dozen or more of the free or paid for AV scanners. I keep going back to avast!. It doesn't treat you like an idiot like most of the commercial products. You can turn off the warning messages if you've disabled a certain feature so you don't get those annoying messages that say, "Your system is NOT secured. You are going to face utter destruction... since you are an idiot etc..".
On the original topic... the typical/average/office/home user would be well served with any modern dual core CPU (as long as it's not Atom: nobody wants to called an Atomite) without any significant hindrance to their usage. Hey, this market can be well served by a 10 year old single core CPU for that matter! As others have pointed out, there are many factors to consider now including whether the processor has virtualisation technology, hyperthreading, its power consumption etc. Price is not the be all and end all, but if something is clearly a ripoff or not worth the trouble, sensible people tend to avoid it.
Sometimes, whether we like to admit it or not, there is an emotional decision involved in purchasing computer parts. While some people couldn't care less, others don't want to use a "bottom of rung part", no matter how cheap or good value it is, or whether it would serve us just fine for what we need it for. To some, 1MB or 2MB cache seems like skimping or a cost cutting measure, which it probably is anyway, especially if it's a quadcore CPU at the lower end of the market.