Learn how to Repair your computer, so it runs stablely again.
I recommend you get CompTIA A+ Certification All-in-One Exam Guide, Seventh Edition (Exams 220-701 & 220-702) to learn more about computer repair since when your computer breaks, you might not be able to go online to search on how to fix your computer. I have used this book many times to learn how to fix my computer, and as a reference on how to maintain and troubleshoot my computer, so I do not have to repair it as often. This book is easy to understand for most non-tech savvy people because the author uses easy to understand words, and there are a lot of diagrams, photos, definitions, tables, and learning aids in this book.
Troubleshooting and repairing a computer can be very difficult since a computer has so many parts which eventually fail. I highly recommend you buy a copy of CompTIA A+ Certification All-in-One Exam Guide, Seventh Edition (Exams 220-701 & 220-702) . This book will teach you everything you need to know about computer trouble shooting, repair, operating systems, networking and more. Plus, if you want, you can take the A+ computer technician exam, so you'll be qualified to fix computers when you pass the exam after reading this book.
The basic tools you need for computer repair is an anti-static strap to prevent static electricity damage and computer tool kit which you can get for less then 30 dollars. If you use your tools from home, make sure your tools are not magnetize since magnetic fields are not good for computers and you may damage your computer with magnetize tools.
You can also get a portable power supply tester to easily test your power supply inside your computer to test your computer power supply.
Having a flash light and magnify glass or reading glasses might be a good idea if your work area is poorly lit, and you have poor vision.
Before you fix your computer turn it off, and make sure you are using an anti-stic wrist strap connected to a bare unpainted metal part inside your PC case like the case, or power supply.
You should also back up all important files which you did not backup yet before you repair your computer if your hard drive and Windows are both still working since there is always a chance of data loss if you somehow damage your PC's hard drive like stabbing your hard drives circuitboard, or hard drive controller port with a screw driver when you are repairing your PC.
Repairing your computer cam be very simple if you know the steps to repairing a computer by reading a book about computer repair. Repairing a PC usually involves disconnecting and reconnecting cables, and unscrewing or unclipping a part from the case, and taking it out, and replacing it with a good part. Lastly, securing the part in place again with a screw or clip.
Parts which I do not recommend beginners and average level computer users replace are motherboards, CPUs, CPU heatsinks, the CMOS battery, and smaller heatsinks on the motherboard.
However, PCI, AGP, PCI-Express, and ISA expansion cards are easy to take out and repair. Memory, PC power supplys, fans, hard drives, CD-ROM drives, Memory Card readers, and floppy drives are not very hard to replace if you read a book and practice how to repair them with a older or broken computer. It is also best to use a broken computer to practice how to insert and take out expansion cards, memory, drives, and power supplies.
Be sure to wash your hands after you fix your computer since computers contain lead and other heavy metals which are not good for your health. It is also best not to touch the metal circuits inside your computer since they contain lead.
A dust mask will be a good idea if the inside of your computer is very dusty. You should use a can of compress air to blow out the dust before you fix your PC.
I like to use YouTube and other online video sharing services to search for tutorial videos on how to fix computers since watching other people fix computer in videos can be easier to understand then reading about fixing computers.