Hello,
Thank you for posting your question on Microsoft community forum.
I appreciate your concern about KB2952664 update.
This update is only related to ease the upgrade from Windows 7 to newer operating system like Windows 8 and Windows 8.1.
Please refer this article:
Compatibility update for upgrading Windows 7
http://support.microsoft.com/kb/2952664
However, Microsoft recommends installing all the important updates as it keeps your computer up to date and prevents it from being vulnerable to any security issues. It also helps in various bug fixes.
I hope this information helps.
Please do let us know if you need any further assistance.
Thank you