Take Care of The Outside of Your Computer
If you take care of your computer, you have less of a chance of Windows XP crashing, losing your data, and cost you money to get it fixed.
The first major thing I’m going to tell you about, is to keep your computer out of the heat and moisture. The hotter it is inside your computer, the faster the circuits will deteriorate.
Before you start cleaning your computer, make sure that there is nothing near it that could raise the temperature of the computer, and clear a spot where there isn’t anything that will fall or make it even dirtier.
Also, make sure you turn off your computer and unplug the computer before you start actually cleaning it. And never, NEVER use a liquid based substance on the inside or outside of your computer directly, use that lint-free cloth by putting the substance on the lint-free cloth and wipe the parts of the computer. Another thing, try to avoid touching the motherboard or anything on the motherboard with your hands or any part of your body, because as long as you have static in you and you touch your motherboard, you will fry it and then it will not start back up, so be aware!
Wipe down the outside of your computer case and use that compressed air can to clean any dust or anything like that on ports, but make sure not to blow it back into the computer where you have already cleaned. This can mean more work and possibly messing up your computer. And make sure that all your cables are attached to the right spots and are done so firmly, not too loose or not to tight. If it is too loose, it will hang in the way and you might end up pulling it instead of something else, and if it is too tight, then if it gets caught on something you are trying to disconnect or anything, it can break a part of whatever it is attached to, and this wouldn’t be pretty.
Is your mouse not messing up on you? If it is a non-optical mouse, then turn it upside down and unscrew the ring by twisting it, it should tell you which way to turn it to loosen it or tighten it. 
If not, then use common sense and turn it both ways until it comes off. Then scrape off any of the gunk that is on the plastic rollers that are ninety-degrees from each other in the mouse.
Some of your keys on your keyboard not going down all the way? Then clean your keyboard as well. To do this, turn your keyboard upside down and shake it. This will clear kind of food, or other little pieces that are in between the keys. But if nothing is coming out and you know for a fact that there is some kind of ‘gunk’ in there, then grab that compressed air again and blast those ‘gunk’ particles out.
Keep your monitor looking good by wiping the monitor case and clean the window with some Windex, or whatever cleaning substance you use to clean any other ordinary window at your house. Also, if you are using an LCD monitor, clean it gently with a lint-free cloth because the glass on LCD monitors are fragile. Has your monitor been near a magnet? Even if your computer hasn’t, you should still do this if your monitor has the function, and that is a degauss button. It will be a small button that has a magnet as an icon. This way, it will clear any interference made by magnets. Clear anything that is blocking the vents without knocking the dust, dirt, or whatever obstruction into the monitor, because if you just knock it into the monitor, it will still be there and will probably just clog it back faster.
If you have a surge protector, check it and make sure all the cables are plugged into it. If you do not have a surge protector, you should invest, they don’t cost much, and buy one. This will help you out incase you have a power outage, because you don’t want lightning to hit your house and take your computer with it!
One more thing that might help you out a lot, is to take care of your CDs and DVDs. You may have important things on your CDs or DVDs, for instance, your computer backups or your Windows XP CD that you use to format your computer. 
To clean them, grab a soft cloth and put a little bit of water on it, and squeeze all the excess water so your not carrying around a lot of water. This way you don’t have to set out a few hundred CDs to dry. Now that you have that cloth, start from the center of the CD or DVD and move it towards the outside, or edge, of the CD or DVD. But never, EVER wipe your Windows XP CD or DVD like you would if you were waxing your car, or these words might be better: circular motion.