Per the link provided by charlesvar, and Arie's post in it http://www.windowsbbs.com/showpost.p...8&postcount=12
it seems "NoExecute=OptOut" is the most secure setting.
Since I have been having no problems with OptOut, I will leave my boot.ini as is.
P.S.--My DEP tab in System reads as did martinr121's in the linked post. The bottom says "Your comuter's processor does not support hardware based DEP. However, Windows can use DEP software to help prevent some types of attacks."