A desktop 4 core PC has Windows Vista (virus) so it suffers from frequent hangs for no apparent reason. No amount of patching and disabling services has cured it.
Microsoft Windows 8 upgrade is currently offered at $39.99, including Media Center upgrade to play DVDs. The upgrade was surprisingly pleasant. As promised, data files were saved and everything else was removed during the clean install. After the install, don't forget to request the Media Center upgrade key.
Screen shots of the Windows 8 upgrade process.
Price and license agreement
Choose to create media or download on the fly
Choice to keep personal files and settings
Personalize color scheme
Express settings, or not
Sign in means to sign in to web account. Downloading apps through web store will require this account.
Begin re-installing applications and customizing.