But for many people, especially those who worked at companies where 401k expenses are high, it could be a waste of money. An easy way to put money back in your pocket is to roll over your savings to an individual retirement account at a discount brokerage, with the aim of getting lower expenses and greater diversification.

Then, as part of a financial plan and budgeting process, you can save money on taxes depending on the order in which you tap your various investments. Always work with an accountant on tax questions, but the rule of thumb is to first withdraw money from taxable accounts, reducing future tax bills. Next come tax-deferred individual retirement accounts, where at age 70½ you'll start taking required minimum distributions. (Will your 401k provide enough? Run the numbers with MSN Money's calculator.)

Roth IRAs make a tempting source to tap first, because you don't pay taxes on withdrawals. "Some people automatically go to the Roth IRA but . . . that should be the last thing you touch, because that money can grow tax-free," says Michael Sadoff, a financial adviser at Sadoff Investment Management in Milwaukee. (Should you convert to a Roth IRA? Check here.)

4. Should I pay off the mortgage?

Paying off a mortgage used to be a major financial goal. Then came the 1990s bull market in stocks and last decade's real-estate boom. Financial advisers began telling clients they'd be better off using their money to invest in stocks and allow rising home prices to reduce the size of a mortgage relative to the equity in the house.

Now, many seniors are saddled with mortgages for more than their houses are worth, thanks to the collapse of the real-estate market.

Still, there's a calculation to be made. How much of a nest egg will paying off the mortgage eat up? Houses aren't liquid investments that can serve as a source of emergency cash.

Also, how does the interest rate on the mortgage compare with what can be earned on a safe investment? Today, that balance tilts in favor of paying off a mortgage, says Roth. "If their mortgage is costing them 5% and they've got a Treasury bond paying 2.6%, then they ought to pay off the mortgage."

5. Who will make decisions for me when I no longer can?

It's never pleasant to contemplate the final stages of life. But doing so is crucial to making a difficult time for loved ones easier.

Retirement is a good time to make sure a will is up to date. But there are other important questions, in the event you can no longer make decisions for yourself -- including giving someone power of attorney to handle business and financial questions and naming a health-care proxy.

It's important to give these questions a lot of thought, says Donald Vanarelli, an elder-law attorney in Westfield, N.J. For instance, does the person you grant power of attorney to live nearby so it's easy to sign documents? When it comes to a health-care proxy, he urges discussing your wishes with the person you name to be sure he or she will be emotionally able to carry them out.

This article was reported by Tom Lauricella for The Wall Street Journal.