You have a problem with your Windows computer and wonder whether its hardware or software. You've tried all the obvious stuff, so what do you do next?
Well before you invest in more RAM, a new hard disk, or take your computer to your local friendly repair man, there is one more thing you can try.
If you boot your computer from another operating system (OS), you effectively get a second opinion. You can do this by downloading a Linux distribution and creating a LiveCD from which you boot your computer.
When you boot from a LiveCD, you are not using the OS on the hard disk, so any problems with the computers OS (e.g. Win7 or whatever) will no longer be an issue.
Let's Create A LiveCD or LiveUSB Stick
Go to: https://help.ubuntu.com/community/Lubuntu/GetLubuntu and download a Lubuntu version for your hardware.
LiveCD: What you have downloaded is an iso which you must burn to a CD as an image, not as a file.
LiveUSB: You need to make your USB stick bootable (i.e. your computer will load and run the OS from the stick).
Go to: http://www.linuxliveusb.com/en/download and download the Linux Live USB Creator to a Windows pc. Now you create the LiveUSB from the Lubuntu iso using the Creator software (See the guide: http://www.linuxliveusb.com/en/help/guide/preparation)
Insert either the LiveCD or LiveUSB into your computer and re-boot. If your computer does not load Lubuntu, you may need to re-boot and enter BIOS to change the boot order, so that the computer boots from the CD drive or USB device (as applicable) first, or at least before the hard drive. Alternatively, there may be an option as BIOS loads to hit a function key (often this is F9 or F12) to select the boot device.
The Lubuntu LiveCD/USB screen gives a number of options.
Select "Try Lubuntu without installing" to run directly from the CD/USB without installing onto your hard drive. It may take a minute or two to boot to the Lubuntu desktop.
There is a new release on Lubuntu every 6 months, so the layout may change with future releases. But for versions up to 12.04 the desktop includes a single panel, either at the top or the bottom of the screen.
To enable wifi, click on the wifi icon and select your access point from the pop-up list. Once you have entered your wifi password, you should see a connection notification, and the wifi icon will change:-
The File ManagerYou can open the file manager via the icon in the panel.
Just about everything in this initial window relates to your "live" system, with one exception.
The computer hard drive is listed under "Places", which in the example above is "158 GB Filesystem". You can open (technically "mount") the hard drive, view files & folders, edit and delete stuff...so be careful!
This is very useful if your computer wont boot from the hard drive due to a Windows corruption. At the very least you can now attach a USB drive and copy all your valuable files, so that you can reinstall Windows without losing data. It is sometimes possible to replace missing or corrupt Windows files via the Lubuntu file manager to get Windows running again.
Hardware Compatibility ProblemsYou may find that the version of Lubuntu you have selected just wont boot on your computer. If this is the case you can try an earlier version, or a different Linux distribution.