NEW YORK (CNNMoney.com) - I recently came into $3,500 windfall from a tax refund and sale of a vehicle and am wondering whether I'd be better off investing this money in a Roth IRA account or putting it toward my $8,000 in credit card balance? I've already been making more than the minimum payment each month toward this debt, but by applying my windfall to the credit card account I'd pay it off even quicker. What do you think is the best move?

- Ray Krick, Gilbert, Arizona

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From a purely financial point of view, the decision comes down to this: Do you think you would earn more on your investments in the Roth account than what you pay in interest on your credit card debt? After all, by using the money to pay off your credit card balance, you would save money in interest payments, and that would effectively be the "return" on your $3,500.

Taxes don't really enter into the decision because your credit-card debt interest isn't tax deductible, while in the case of the Roth your return is tax free, provided you meet certain criteria. This means you're getting after-tax returns in both cases, so it really comes down to which return is higher.

You don't say what you're paying on your plastic, but according to the credit card section of Bankrate.com, interest rates have been recently averaging anywhere from 10.1 to 14.3 percent, depending on the type of card you carry.

It's possible, I suppose, if you were an extremely skillful (or lucky) investor, that you could average that sort of return over several years. But I doubt it. So that would seem to make paying down the credit card the better choice.

But you know what? I don't think that would necessarily be the smart thing to do. In fact, I think there's a strong argument for opening the Roth anyway, if not with the entire $3,500, then at least a good portion of it.

Here's my thinking. One of the biggest problems we face in America is that we just don't save enough for retirement. You can find any number of reasons for this - it's easier to spend than save, we're too into immediate gratification, etc. - but one way or another it ultimately comes down to the fact that we don't stick enough money into savings accounts, including Roth IRAs.

But here you are with a chance to stick $3,500 into a Roth, and you're willing to do it. My feeling is, hey, carpe diem, baby! Seize the opportunity to jump start that retirement account while you can.

Otherwise, who knows? If you put the $3,500 toward your credit card balance, maybe you'll finish paying it off more quickly, or maybe you won't. Maybe after paying off the credit card you'll start funneling money into a Roth or other savings vehicle. Or maybe you won't. Maybe a few months from now you'll see some nifty new gadget you want or you'll decide to reward yourself with a nice vacation or whatever and use the convenient plastic currency.

My point is that since it's easier to spend than save, credit card balances have a funny way of creeping up again. And if that happens, well, you could find yourself back where you were with the same level of debt (or something close to it), but without any money socked away in the Roth.

So my advice is open the Roth. You don't have to put the whole $3,500 in. You could always take a middle course and put $1,750 into the Roth and $1,750 toward your credit card account. This way you chip away at your balance and at least you've also got something socked away toward retirement.

Whatever decision you make, keep up your plan to pay more than the minimum payment so you can rid yourself of that credit card debt more quickly. In fact, rather than just paying more than the minimum, why not set a goal, such as paying off your card balance within a certain amount of time, say, a couple of years. You can find out what size payment you need to do that by clicking here.

One more thing. Once you pay off your balance, take the money that you had been putting toward your plastic debt and save it. After all, you haven't been using that money for living expenses, so you can obviously get by without it. So instead of finding new ways to spend it, why not use it to build a nice nest egg? Come retirement time, you'll be glad you did.

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