The good kind of computer freeze

Previously, after having issues with my computer being buggy, slow, or even outright hijacked and infected, I've had to run numerous programs to try to de-infect it, like anti-virus, anti-spybots, anti-hijack, anti-fishing, etc programs. And when you're running AVG, Search and Destroy, Windows Defender, Trojan Hunter and a bunch of other junk, that in itself must be responsible for some of the system slow down. Plus, I could never tell if they were really working. For the most part, they found nothing. And I'd also run HijackThis, which creates logs of system information that you have to interpret, sort through, prepare, and then if you're still stuck upload to a forum, where other people would tell you what to do to clean up the computer before they'd even look at your log, and then after that you'd get advice on what to 'fix' (which is at least a simple final thing to do) from the log.
So after getting sick of that, after spending a decent chunk of my time on the computer 'protecting' it, I switched to the Firefox browser, figuring that most of the problems where from web codes and the like. And then when Google Chrome came out, I figure, well, this is so new and represents such a small percentage of the browser population, its probably not much of a target and might be safer too. But still, after a long while, I think that bugs and malware and the like have just accumulated, and thats why I reinstalled my Operating System recently.
Our college campus loans out laptops to faculty for the semester. In order to protect the laptops, they flash out their memory each time they are shut down, so that when you turn it on, anything you did to it is gone, any files you saved, and preferences you changed, are all gone, its in its original state. This is done by 'freezing' the computer. I thought at first that that was just ridiculous, having to save everything to a thumb drive and not being able to set any preferences. But recently I realized, maybe that is what I need. If my computer just snaps back to its original state each time I shut it off, then I don't have to worry so much about viruses, malware, etc. So thats what I've done, I've frozen my computer, set it so that anything I need to keep is saved somewhere else, and thats it. I still have antivirus, firewall, etc. I am just trying to see if this is a workable solution, I think that it will be.