Richard, in your question, you mentioned having received a great many blue screens, but gave no indication as to what the blue screens say. Therefore, I?m going to proceed with the part of your question where you ask how to wipe and do a clean installation.
In my experience, a clean installation of any operating system is better than an upgrade. The new OS doesn?t inherit any of the problems of the previously installed operating system. Assuming that your data is backed up, the process is simple: Place your Windows disc into your DVD drive and let your computer boot from it. When asked, just choose the option for a new installation of Windows 7. At some point, the installation process will ask for your Windows Vista installation disc to verify that you are eligible for an upgrade. And don?t worry: As far as multiple uses are concerned, you are allowed to install the same copy of Windows to the same machine as many times as you need. If in the unlikely event that the authentication fails, there will be instructions as to what to do next. Simply explain the situation to the representative and they?ll remedy the situation.
The exception to doing a clean installation is when drivers for Windows 7 (such as video, audio, networking, etc.) are not available from either the manufacturer of the computer or the vendor who supplied the component. I personally ran into this issue recently when I found that Compaq has not yet released Windows 7 drivers for any of my laptop?s components. Where video drivers are concerned, I found that Nvidia refused to install any kind of upgrade, suggesting instead that I refer to the manufacturer of my laptop. In that case, my only option was to upgrade from Vista to Windows 7.
If you run into the same situation, then start off with a clean installation of Windows Vista. If your computer came with Vista, then you should have a recovery CD or a recovery partition on your computer?s hard drive. If you?re uncertain how to access this partition and start the recovery process, then check your computer?s documentation or search online for the make and model of your computer, and the phrase ?how to restore? (be sure to use quotes with the phrase ? it makes a difference with the search results).
Where patches are concerned, make sure to install only Windows Vista Service Pack 1. Vista SP1 is necessary in order to continue the upgrade process. Ignore all of the other patches for now. Once that's complete, proceed with the Windows 7 upgrade by running the installation process from inside Windows Vista. Be sure to let it check for updates to the installation process.
Be warned that you will need several hours to complete this process, so be sure you?ve set plenty of time aside for it. In the end, and barring any unforeseen difficulties, you'll have a smoothly-running computer.
Good luck!

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