2GB RAM on Win7 64-bit. Seems most of the free RAM (up to 1GB being reported as being used in Task Manager) was being chewed up by one of the svchost that includes "Windows Update".
Killing the Windows Update service and changing it to manual has "fixed" the issue but obviously we need updates and this is for my mother-in-law that just wants to open Outlook and the odd document/image so asking to do updates manually once a week isn't a fix.
I want to exhaust all avenues before saying "buy a new computer" as her needs are so small in comparison to you or I.
QUESTION: Is there a way to have the windows update service not running but schedule the task to run once a week? e.g. scheduling wuauclt.exe with these switches https://technet.microsoft.com/en-us/library/cc708617%28v=ws.10%29.aspx