Risk v. Reward in the stock market

[maxtower]

I like index investing, and I am planning to put some significant cash into an index in the near future. Does anyone have any good information on which stock market indicies are the least volatile. The S&P 500 may be too swingy for the return it offers. Would buying the Russel 1000 Value or 2000 Value offer less risk with the same or better rewards? How about the Mergent Dividend Acheivers? It has beaten the S&P since 1983.
It just seems to me that one of these more value oriented stock indicies can beat or match the S&P returns with less risk. I am looking for some historical data to back that up. I did a little research on the internet, but most info only contains data from the last few years. I was hoping for something more long term.