unable to access internet explorer or norton website

when i attempt using a search engine on my PC, IE/MSN/Xfinity, i get a pop up screen from windows stating

"IE has stopped working

Windows Data Execution Prevention detected an add on trying to use system memory incorrectly this may be malfunction or a malicious add-on"

Norton 360 is being blocked, unable to scan or clean

i am entering this on my lap top in hope that someone may be able to instruct me on a simple solution otherwise it's back to service with the tower.