verrouillé Bad LAG with Windows 10

This lagging started almost immediately after the download of Windows 10 - everything on my computer is slow.  Programs take a while to open, then when open, sometimes I can type faster than the computer can keep up!  I cannot figure out what to stop 'running in the background' -- but it just feels like something is dragging the speed down, but it's not showing up in the "Remove Programs" part!  I use few applications -mainly MS Office, Adobe Reader, Photoscape, Picasa, and a browser (Chrome) for the Internet. They are ALL lagging!  I've disabled some things I found that I never use but am fearful of deleting much else!  Or disabling it.  But SOMETHING has to go!  Maybe ... Windows 10 in its entirety?  I much prefer Win 7!  THANKS for any help!