Personally I use a PC, not because I think it is better than a Mac, but because its my choice of preference. Here I'll list some programs that I use as tools whenever my PC has problems. This is mainly based off my own experience using a windows.
Many times we download software without making sure if its virus-free. In some cases we blindly click on a download button, that truly isn't a download button.
Most of the time PC errors occur because of Malware, Trojan Horses, Spyware, viruses, and more. If you start to notice that your PC is acting funny, freezing, opening apps constantly (that you don't recall installing), or giving you the blue-screen of death, then some of these tools may be very helpful to fix or prevent that.
The following applications are FREE. Unless you want to upgrade, but in my experience I haven't had to pay for the following:
Download - Malware Bytes
This application has helped me fix my PC many times. If you ever see that your computer starts opening random software you NEVER installed, or your PC keeps freezing, or telling you that you NEED to download a PC-Protection software, then in this case you have some MALWARE, or TROJAN horse. These can be really annoying!
The best thing to do is to have Malware Bytes installed from the beginning of the time you use your laptop. It's always best to run this application in critical cases like those under SAFE-MODE.
AVG Anti Virus
Download - AVG Anti Virus
This free software is great in catching viruses or any type of malware, and its FREE. It runs in the background. It scans through files you have downloaded, and even notifies you if anything of a threat is infecting your machine. I always install this application when I have a new PC. As you begin installing applications on any new computer, this will scan files as they are downloaded to keep you safe. Its a must have application if you need some free software protection.
Download - CCleaner
Overtime your PC gets cluttered with many files, and in most cases causes your computer to slow down. Which is normal, but we of course want our PC running fast and smooth. Think of it as an oil change for your car. We get one every 3 months or so, at least, I do. I tend to run this application every so often to keep things smooth. It allows you to choose what to delete and what to keep.