Malware scans? Antivirus? What are these things? Oh wait, hmm, it's coming back to me.. about 9 yrs ago I dealt with those problems, then switched to the scary Linux..
--informative rant--
Nowadays people can just download an iso, burn it, boot from the cd, and with 6 very simple steps erase the virus (I do mean MS Windows), and have a safe and fast operating system, all for free. It's even easier than installing windows, no need to input a cdkey. Just make sure to backup all your images, documents, and videos on a seperate drive (cd, external, flash drive, secondary hard drive, whatever) first.
The _ONLY_ group of people that (CAN'T) do what they "NEED" in linux are hardcore gamers that only play the latest and greatest games. Web browsing, flash (youtube etc), yes - even porn sites, torrents, office work (Full featured spreadsheet applications, document writing programs, light to heavy duty database applications, scientific calculators), are all standard features.
With wine one can even run many many "windows only" programs, including MS office, world of warcraft, and tons of other stuff. Kubuntu is my preferred, but many like the gnome feel of regular Ubuntu. Did you know KDE had widgets long before windows? Did you know compiz (Now compiz-fusion) was doing advanced desktop graphics stuff (Like wobbly windows, window previews, desktop zoom, previews in alt+tab, window transparency, and tons of other features) years before windows? I only mention Ubuntu and not any of the plethora of others simply because it's the easiest to set up and use with very little messing around (best for beginners, and people who don't want to waste their time).
--end informative rant--
--Useful information on fixing most common windows problems following--
All that being said like a (wonderful) commercial, to many people are to scared to run anything else. "It's all I know." or "I don't have time to learn to point and click in another OS". Which makes me money because, I go out with a cd(or flash drive) containing hijackthis!, combofix, google-chrome installer (Because IE is so crap), and one or two other tiny utilities from bleepingcomputer, and typically make $50USD a pop for an hour (With only about 5 minutes actually interacting with the computer). Once in a long while I need to open the registry and find the RunOnce section to locate a piece of malware that's not detected due to somebody changing a few bits in the header of the program with a hex editor..
And for that, I thank you all.
Sorry for going on so long. It's a passion, if you can't tell.