(1) Will Avast at the same time clean virus when found one ?
yes if u have the vrdb ( a database avast creates every month or every weeks or every hours
(2) yes turn on check created& modified
(3) i almost sure , yes
(4) norton residend shield uses a vxd , and it runs with the operation system , so it's better if u uninstall it
u will miss nothing , NORTON is a CRAP