http://www.technipages.com/windows-enabl...superfetch
Disabling superfetch will allow you to become a pony... Well disabling it will free your RAM and (hopefully) CPU usage since I am not quite sure where the high CPU usage comes from (will need some event logs but superfetch might solve this issue anyways)
Always make a backup before changing anything on your system...
Never close svchost, since if it would be a virus you would notice it (really...)
@chckdsk and MemTest: Chckdsk is useless in this case. It is used when someone has problems with his HARD DRIVE DEVICE / SSD but DEFINETLY NOT when someone is having RAM and CPU issues like the OP. MemTest too since it does fe the RAM..
EDIT; Two of my PCs (Win 8.1 Pro/Windows 7 Ultimate) had superfetch disabled by default, as side note.
EDIT 2; The reason why mine was disabled on both are the SSDs installed (Using Samsung Magician it disables the feature automatically to improve SSD lifetime)
