Lifestyle Funds for the Inert

Know yourself. These funds, as the name suggests, are designed to fit a particular lifestyle -- not just how far you are from retirement age, but also your investment temperament.

"Investors really need to know how much risk they can handle -- you shouldn't put your money in an aggressive growth lifestyle fund if it means you can't sleep at night," Meyers said. Firms generally offer four or five funds -- for the conservative to the aggressive-growth investor.

"Investors can't be absolved from doing the initial work to decide what angle works for them," said Langdon Healy, a mutual fund analyst at Morningstar. Meyers said the middle-of-the-road choice -- moderate growth, with a usual mix of 60% stocks, 30% bonds and 10% cash -- is a good bet for most investors who have a ways to go before retiring.

The tradeoff. Lifestyle funds aren't designed to beat the market, giving you hot returns and bragging rights at a party with your friends. If you really want that, good luck and God bless -- but know you have to put more work into it. If you want to choose and go away for 30 years (except to check your holdings, say once a year, with some of these options) and end up getting an average annual return of about 7% or so, these are your best bet.

Here's a look at three of the best lifestyle fund series.

1. Fidelity Freedom Series

Fidelity offers five Freedom funds with a year as part of the name, such as the Fidelity Freedom 2020 fund. Investors typically choose the fund whose date most closely corresponds to their retirement date. Fidelity achieves your proper asset allocation by choosing a blend of their own funds. The Freedom 2020 fund, for instance, has 18 funds under its hood, working out to a mix of about 63% stocks, 31% bonds and the remainder in cash and other investments.