Hey t11allen,
To turn on/turn off your hosts file (or, as you put it, to control it like a light switch), go here, scroll down about halfway, and download "
RenHosts.bat":
http://www.mvps.org/winhelp2002/hostsfaq.htm#Rename
It is a simple command prompt batch file that I think will do what you want.
Actually, there are a few other utilities on that site (scroll down to the bottom) that will also do what you want. I use the "
RenHosts.bat" and am satisfied with it, but you may prefer one of the other ones.