Glaze-over alert! Glaze-over alert! NBC News doing "White Paper" on pension funds! Dumping it in traditional documentary burial ground -- Saturday night time slot! Steve Delaney to anchor without ever changing expression or tone of voice!

Forbidding as it sounds in concept, "The Biggest Lump of Money in the World," tonight on Channel 4 at 10, is probably as engaging and plain-talking as a documentary on pension funds could be, assuming there ought to be one in the first place. Certainly the importance of the subject is established up top: pension funds now total more than $1 trillion; majority ownership of all common stock in America will reside with them by the year 2000; more than 100 billion new dollars are invested in the name of pension funds each year.

All this is dutifully explained and illustrated, but one dilemma the documentary faces is that it's dealing with a very literal dollars-and-cents issue that nonetheless seems as graspable and concrete as the pixie dust parceled out by Tinkerbell. All this money that is moved about from company to company, investment to investment; does it really exist? Or is it just numbers in a computer?

A computer named Fred actually does the investing, makes the key decisions, at one money managing firm. Delaney explains that the Employee Retirement Income Security Act, which reformed the care and feeding of pension funds by employers and established retirement guarantees for workers, has spawned an industry of money managers who sit at their computer terminals wheeling and dealing all day. "Whoo, Apple down five-eighths!" we see and hear one of them saying.

Their power and wealth has led to such ironic developments as a building trade union's pension fund being invested, much to the anger of union leaders, in nonunion construction projects. The goal of money managers is supposed to be purely and entirely to make more money for the investors, but now there are growing pressures to politicize investment, to use the enormous clout of the pension funds to effect social change, as in refusing to invest in companies that do business with South Africa. This is the most provocative prospect raised by the documentary, but it comes a tad late in the hour.

Reuven Frank, who produced the report, worked ingenious wonders with such previous documentaries as "If Japan Can, Why Can't We?," making intricate or arcane economic matters not just comprehensible but fascinating to Joe (and Jane) Viewer. But pension funds remain a largely inscrutable lump even with production expertise and resourcefulness brought to bear, and Delaney, also the writer, is an able reporter who unfortunately has difficulty imparting even a hint of a wisp of a rumor of urgency.

The documentary doesn't quite answer the most basic journalistic question: Why are they telling us this now? It tends to waltz around the room with it instead. Much of the waltzing is engrossing, and the program's entree into what is for many of us an absolutely alien world, ambitious and penetrating. But a money manager offering his opinion on using divestiture as a social force may be speaking for many a baffled viewer confronted with impenetrable matters of high finance when he says simply, "To me, it's a farce." 'Blackout'

When it comes to original production, Home Box Office specializes in the semi-lousy movie. It isn't bad enough to make you get up and run out of your own living room, but hardly ever good enough to make you want to cancel all plans for the evening and stock up on microwave popcorn. "Blackout," which premieres on HBO Sunday night at 8, is a moderately competent thriller riddled with red herrings, plot potholes and cheap scares.

Richard Widmark plays a surly, and unnecessarily foul-mouthed, small-town police chief stymied by the multiple murder of a woman and her three young children. The corpses, in a deftly grisly touch, are all propped up in front of a television set as if still alive. Six years later, retired from the force but still obsessed with the case, the cop encounters a man he feels certain is the killer.

That chap, played by Keith Carradine, is an amnesiac who was disfigured in an auto accident not long after the killings took place. Plastic surgery has given him a new face and he has even founded a new family, including a wife played in her usual consummate-abysmal style by jittery Kathleen Quinlan. Like the suspected killer, her hubby is a realtor with a thriving business and good reputation.

David Ambrose's script provokes questions it doesn't intend to provoke, such as how in the world does the accident victim, whose entire identity has been wiped out, ever manage to pay his hospital bills for a year of reconstructive surgery? The plotting is herky-jerky, and the introduction of a rapist in a leather mask an utterly gratuitous 11th-hour gimmick. Director Douglas Hickox makes some of the big scares pay off, but no Hitchcock Hickox; he can't sustain a pervasive or distinctive ambiance of dread.

Indeed, during one flagrantly expendable scene involving an extortion attempt, I found myself watching not the actors but the moving letters on a motel sign that could be viewed in the distance through a window. It said, in part, "Hit Movies Via Satellite." Imagine! Somebody really ought to start a service like that. 'One on One'

John McLaughlin's "The McLaughlin Group" is the "Rambo" of political talk shows, a kookie quantum leap forward for the genre, but blustery John's "One on One" tends to be a fairly standard interview program. This week, however -- Sunday morning at 11 on Channel 4 -- the guest is Nancy Reagan, giving her longest broadcast interview since President Reagan's successful cancer surgery.

Although anything but an unfriendly questioner when it comes to Reagan administration personalities, McLaughlin really is as tough on Mrs. Reagan in this chat as anyone would want him to be at such a delicate moment for her. She seems composed, confident and optimistic but, as often during such interviews, maddeningly reticent. Some simple questions appear to confuse her. One of the mysteries about Mrs. Reagan is whether she is cunningly diplomatic in these situations or actually inarticulate.

McLaughlin plunges bravely on. Mrs. Reagan's strongest opinions are reserved for doctors who were commenting on the president's surgery for the networks while he was in the hospital. "I have problems with doctors who had nothing to do with the case . . . going on television or the press and talking about it," she says. "It's unethical. You don't do that when you're a doctor . . . It's unprofessional."

Mrs. Reagan defends the treatment her husband got at Bethesda Naval Hospital ("we had good care there") and says she does not feel physicians or presidential advisers erred by not insisting Reagan get a more thorough examination in May 1984, when the cancer might conceivably have been discovered at an earlier stage.

During McLaughlin's inevitable political gossiping, Mrs. Reagan sounds at least slightly disingenuous. Has Donald Regan become America's first prime minister? "I don't get into anything like that," Mrs. Reagan answers. "Really. I would have no idea if that's true or not true." McLaughlin gets a bit silly when he starts questioning her about "aid to the contras." She says of her relationship with the president, "Where I involve myself mostly is with the whole people aspect -- if I think somebody is trying to take advantage of him."

McLaughlin doesn't return from this expedition with any great booty, but it's certainly not for lack of persistence. Mrs. Reagan remains an elusive interviewee. Good luck to the next challenger.