May 12, 1984

The booming use of personal computers is enabling thousands of small enterprises - lumber yards and law offices, small banks, shops and farms - to do a better job of running their businesses. With a speed and precision that was once enjoyed only by the nation's largest companies, they can now figure finances, control inventories and compute costs - in short, get a better grip on their own business destiny. ''There is nothing the computer does that we couldn't do before,'' said Albert P. Oliveira, who uses it to track a score of salespeople for the Equipment Sales Company here in Lowell. ''But it is so incredibly fast, and easy, that we can do far more.'' Driving this headlong overhaul of business practices are not the small computers themselves, but the remarkably popular genre of personal computer programs known as electronic spreadsheets.

The Central Elections Council today declared Jose Napoleon Duarte, the moderate candidate, the winner of Sunday's presidential election. He received almost 54 percent of the vote. The far-right opposition party said it would not accept the council's tally. ''The elections don't have any credibility and the results are a farce,'' said Hugo Barrera, the vice presidential candidate for the right-wing Nationalist Republican Alliance, known as Arena. ''In no way will we accept the victory of Duarte.''

Irony, inevitability and miscalculation marked the Chancellor's precipitous downfall. Page 14. Anthony John Alvarado resigned yesterday as Chancellor of the New York City school system, four days before he was to face a disciplinary hearing on charges of professional misconduct. His resignation was offered with a ''sincere and profound apology to the city I love and its citizens, whom I deeply respect.''

Sales at the retail level surged 2.9 percent last month, the Commerce Department reported today. The Administration hailed the report, but economists said that it could mean fresh increases in interest rates soon. They noted that much of the sales growth had occurred in so-called big-ticket items - cars and appliances, for example - that are generally bought on credit. This exacerbates the competition for financing.

Eight people were killed and seven others were injured last night in a fire at a haunted house attraction at an amusement park in Jackson, N.J., according to authorities. The identities and ages of the dead were not immediately known. The victims were believed to be teen-age visitors at the park - Six Flags Great Adventure - according to the Jackson Police Commissioner, Richard Borys. He said that as of midnight the bodies still had not been removed from the rubble of the building, which was destroyed.