what programs need to run in the background?

System Idle Process

explorer.exe

taskmgr.exe

spoolsv.exe

lsass.exe

csrss.exe

smss.exe

winlogon.exe

svchost.exe – (There will be a few of these)

services.exe

By shutting down anything other than these processes, stand alone Windows should operate fine, however if any of these processes are shutdown, Windows will start to become unstable or unusable.

To shutdown a Windows process, Press Ctrl+Alt+Delete, Goto the Processes Tab, Select a process and click End Process.