Over Protect Because Failure WILL Happen
Maybe it's a little overkill, I'll admit but I've lost precious data to a failed hard disk drive before and now I'm almost paranoid about it to the point I have 6 hard disks spinning plus an off site backup...
Most people using computers think having virus protection (which is NOT optional if you're online) is all they need to protect them. Not so. I want to share with you what I've learned and let you decide if you're safe.
1- Back up your data. It doesn't matter how good your system is or how good and/or expensive the software is. None of it will prevent a mechanical hard drive failure. You need to back up to A) A second external drive B) An off site service like Carbonite (which I use) or C) a network drive. Preferably, you should use at least 2 of the 3.
3- There are some excellent spyware/malware standalone programs that are free. One I use and recommend is Spybot Search And Destroy.
4- Use your operating system's built in features. Windows has "defrag" and "error checking." Just right click on the drive letter in Windows Explorer and select properties then the "tools" tab. You should run these programs at least once a month if not weekly to keep things running smoothly and fast.
5- If you're an advanced user of Windows (xp, Vista, 7 or 8), here are some all around utilities that are free and pretty effective. Glary Utilities and Advanced System Care. I use both of these and they are great at keeping all sorts of things, including the Windows registry, in good shape. By the way, before you EVER allow a program to make changes to the registry, if it offers to back it up first, always select yes. And while I'm on the registry subject, CCleaner is another excellent and free product.
6- Finally, and this is a biggie, click "start" and in the text box, type "msconfig." When the program starts, hit the "startup tab." Uncheck whatever you see that you KNOW you don't need. If you're unsure leave it checked. Programs that start when the machine does are the biggest drain on system resources and many of them are added by other programs. Some to trace your habits, some to make start time for a particular program faster and others can be malicious. If you have a really slow system with lots of "junk" starting, take it to someone who can look at it and clean it up.
That's my two cents. I do love computers and did study them so I do have some knowledge of what I'm talking about. I wish you well :-)