Try this thought exercise. It's about your future and that of the US economy: You have been getting raises for several years. Your household budget is, for the first time in decades, in the black. You face a choice on what to do with the excess of income over regular expenditures. You may: 1. Put the surplus into your 401(k) or IRA saving account for retirement. 2. Pay down mortgage and credit card debt. 3. Budget more for rising health insurance premiums. 4. Remodel the kitchen, repave the driveway, buy Web access, replace the old polluting furnace. 5. Vote bonds for new schools and police needs. 6. Contribute more to charities. Big decision. Not unlike that facing the White House and Congress. President Clinton announced last week that the federal budget will post a $76 billion surplus this year - its second year in the black after three decades in the red. He again appealed to Congress to use the money to "save Social Security" - the equivalent of option 1 above, tucking away the surplus for retirement pensions. Fine. Except that the president added to his appeal for Social Security rescue a Pandora's box phrase: plus "a lot of other challenges." As Americans saw last year, both the White House and Congress eagerly classified a long list of projects "emergencies" in order to skirt agreed budget limits. Result: Nothing was done about saving SS, but the surplus was eaten into by projects ranging from near-emergency to pork. Alas, this year both the president and Congress have reason to add more such surplus-eroding favorites to the list. Mr. Clinton to show he's doing the people's business; Congress to show it's not so fixed on impeachment it can't get other things done. Remember, the economically savvy baby-boom president has long been aware of coming boomer retirement pressure on SS but did nothing about it in his first term. Recall that he did little more than hold a few meetings last year after pledging to save SS (to head off a big GOP tax cut). Neither has Congress rushed to take action. That suggests a different tack: that the best use of surpluses in coming years is primarily but not exclusively option 2 above, to pay down national debt. That would free up capital lending for innovative businesses that generate jobs, income, and tax revenues. It would also shrink the weight of debt service on federal budgets. And that would allow future politicians more flexibility in funding the national budget options that roughly echo the six household budget categories: SS pensions, Medicare, education, defense, infrastructure, environment, and the social safety net. It would also, incidentally, let this president and Congress show they're doing the people's business wisely.