There is no question about it: PCs are so much a part of our lives nowadays that they are almost indispensable in many homes. That said, they do come with their own problems, and it often seems like the time it takes to fix a PC problem exceeds the time saved by having the computer in the first place.

However, with a little insider know-how, it is often quick and easy to mend common problems. Over the next few pages we take a look at some of the most common problems that afflict PC users, and show you some handy five-minute fixes that will get you out of a jam.

Problem: The computer is running slowly
Your computer works reasonably well but it runs slowly all the time. It was quite a lot faster in the past but it now takes a long time to start up, shut down or get anything done.

Slow PCs can be caused by several things. Make sure all your drivers are up to date (check the hardware makers' websites), and see www.windowsupdate.com for the latest Windows patches.

If you installed any software just prior to your PC slowing down, try uninstalling it to see if that cures the problem.

Make sure that the computer's hard disk is not full. Windows uses parts of the hard disk heavily in daily use for Virtual Memory, so you should have a large part (at least 1Gb, if the drive is larger than 10Gb) free for its use. To change Virtual Memory, right-click on My Computer, select Properties and then click on the Advanced tab. Click on Settings in the Performance box, select the Advanced tab and click on the Change button and then check, and change if required, the settings. Also, try defragmenting the hard disk with the tool built in to Windows. Click on Start, then on All Programs, Accessories, System Tools and finally Disk Defragmenter.

Problem: Can I undo any changes I have made to the computer?
Usually you don't have problems when installing new programs, but there are occasional troubles. Is there a way to go back to how the computer was before installing a program?

Windows includes a tool called System Restore that will do exactly that. It can be used before installing new programs to make a record of how the computer is set up, and if there are any problems, it allows you to revert the system to how it was before.

To use it, click on the Start button, then on All Programs, Accessories, System Tools, then System Restore. Click on 'Create a restore point' and follow the instructions. You may be asked to enable System Restore first, in which case follow the instructions.

To restore the computer after installing an application, go to System Restore again, as above, and click on 'Restore my computer to an earlier time' and follow the instructions. Any recently saved files, email or internet bookmarks should remain as they are and will not be deleted, but any programs installed since the restore point was created will be removed.

Problem: Programs or music CDs always start when I insert a CD in the PC
When you put a disc into the PC it sometimes runs a program or brings up a menu asking what you want to do with the files on the disc. Is there any way to change what happens when you put a disc in, or turn this feature off altogether?

This feature is known as Autoplay and it controls what happens when a CD, floppy disk, USB key or portable hard disk is inserted into the computer. If the disk or device contains certain types of file, these will be automatically started when it is inserted.

To temporarily stop this from happening, simply hold down the Shift key on the keyboard at the same time as you are inserting the disc. Release it once the light on the front of the drive has stopped flashing. To turn it off permanently, you need to download and use TweakUI (/2128680).

Once it's installed, run it and go to the Paranoia tab, then remove the tick from the label 'Play audio CDs automatically' and 'Play data CDs automatically', then click on OK. To change the function of Autoplay without turning it off, open My Computer and right-click on the device in question, then click on Properties. Click on the Autoplay tab and follow the instructions.