Channel 20 has moved "The Mystery of Al Capone's Vaults" from 9 p.m. on Monday up to 10:30 p.m., or following, the conclusion of the Caps-Rangers Stanley Cup playoff game that night . . .

The "live" two-hour syndicated show will actually air at 8 p.m. on the East Coast as workers, with host Geraldo Rivera standing by, open vaults beneath Michigan Avenue at the Lexington Hotel in Chicago, where gangster Al Capone maintained his headquarters . . .

The vaults were discovered in 1981 and the IRS already has a lien of $800,000 on whatever is found in them . . .

WDCA had signed with the Tribune Entertainment Co. some time ago to air the show, with a rerun scheduled for later this month . . .

Both sides were aware of the upcoming Stanley Cup games, but the surprise entry of the New York Rangers changed the nightly schedule . . .

With WDCA's approval, Tribune Entertainment, which has made a considerable investment in the special, reportedly offered the special to other stations in the Washington market to get prime viewing time. There were no takers . . .

In a most unusual move, WDCA even offered to air promotions for the broadcast on another station during the Caps-Rangers game Monday night if the move were made . . .

Yesterday, WDCA and Tribune Entertainment agreed that it could run on a delayed basis following the NHL game . . .

Tribune Entertainment, which aired the Andrea Doria safe-opening special in August 1984, says "Vault" will be the biggest syndicated special ever, airing on 181 stations, half of which are network affiliates, and covering 95 percent of the national TV audience . . .

Some 40 ABC affiliates have signed for the special. As a result, according to a Tribune spokesman, ABC moved the movie "Alex: The Life of a Child" from Monday to next Wednesday night instead . . .

The Rev. Jesse Jackson, who accused CBS of "de facto apartheid," has announced his Rainbow Coalition is joining a boycott of the TV network and CBS-owned stations to force the hiring of more black executives and weekday news anchors . . .

The CBS stockholder and former Democratic presidential candidate told about 300 shareholders Wednesday at the network's annual meeting that "the issue is fairness and equity, and our long-suffering and patient negotiations have not brought forth a remedy" . . .

The civil rights group, which Jackson started during his 1984 campaign, joins a boycott started by another group he founded, Operation PUSH . . .

The boycott began in September when a black anchorman at CBS-owned WBBM in Chicago was demoted to make room for Bill Kurtis, returning to the station after a stint with "CBS Morning News" . . .

PUSH initially targeted only WBBM but expanded the boycott nationwide in February . . .

Thomas Wyman, CBS chairman and president, said management was ready to discuss the issue and find solutions . . .

"We have broken some ice," Wyman said, citing the appointments of members of minority groups to executive jobs, including the post of general manager of WBBM . . .

"If [President] Reagan's Cabinet was composed of all white males, it would be attacked by CBS," Jackson told the meeting in Philadelphia. "PUSH is raising a simple question. Can the news media withstand the same standard of judgment that it applies to others?" . . .

Jackson called on the company to negotiate an agreement setting goals and timetables for more minority hiring and programming . . .

"De facto apartheid in this corporation must be a source of embarrassment and shame to every shareholder and a source of sinister joy to the Republic of South Africa," Jackson said. "I urge an immediate commitment for a remedy to this" . . . Also in the News

Sen.Paul Simon (D-Ill.), angered by accidentally viewing someone "sawed in half in living color," introduced a bill yesterday aimed at pushing the television industry into dealing with violence in programming . . .

The bill, which would provide an exemption from antitrust laws to permit networks, independent stations and the cable TV industry to work out guidelines on violence, was cosponsored by Sen. Strom Thurmond (R-S.C.) . . .

"We're seeing too much violence on TV for our own mental health," Simon told a press conference, adding that he became aware of the problem when he switched on a TV set in a motel room and saw a gruesome scene from "The Texas Chainsaw Massacre" . . .

"Someone was being sawed in half in living color by a chain saw and it bothered me," he said. "I'm 57 years old . . . but what happens to a 12 year-old?" . . .

The bill, which is generally opposed by broadcasters, would also order the Federal Communications Commission to study the problem . . .

ABC Entertainment announced yesterday that "Mr. Sunshine" moves from Friday night to 8 p.m. Saturday on May 3, replacing "The Redd Foxx Show" . . .

On May 9, ABC will introduce a Friday night movie, which will start either at 8:30 or 9 p.m. each week . . .

"Joe Bash," which airs at 9:30 Fridays, will have its last outing on May 2 . . . Likewise, "The Fall Guy," which airs at 10 p.m. Fridays . . .

The first Friday movie will be "Thunderball," which will air at 8:30 p.m. May 9 . . .

"Today" continued its winning ways for the week ending April 11, recording a 5.8 Nielsen rating and a 25 percent audience share, compared with a 5.2/22 for "Good Morning America" and a 2.9/13 for "CBS Morning News" . . . Oh, What a Feeling!

With its first-ever regular season primetime win staring NBC in the face when the Nielsen and Arbitron figures are released next Tuesday . . . just how does the House of Hits plan to handle the monumentality of it all? . . .

"We will try and be tasteful," NBC Executive Vice President for Corporate Communications M.S. (Bud) Rukeyser Jr. said yesterday . . .

"Oh, there'll be a little jumping up in the air, maybe some clapping on the back," he surmised. "But there will be no gloating ads. It will be, as you might expect, all done in a classy, gentlemanly way" . . .

NBC expects to win by nearly a full rating point over second-place CBS, last year's champ . . .

Monday night in Hollywood, NBC Entertainment President Brandon Tartikoff will host a dinner to mark the occasion, according to Rukeyser. Among the invitees: former NBC chairman Fred Silverman . . .

On Tuesday, upon arrival of the official ratings, Tartikoff will appear on a satellite hookup with NBC affiliate stations around the country where local press will be gathered to ask questions (Captain Airwaves has already prepared his question for Tartikoff. "Mr. Tartikoff," he'll say, "how does it feel to be number one?") . . .

NBC has staged three such satellite hookups previously, but for the first time all affiliates in the top 20 markets will participate . . .

Later in the week, NBC on the East Coast will celebrate with a cocktail party in Manhattan . . .

Well, yes, NBC Entertainment would mightily like to have a "Return to Mayberry II" TV movie in the works but right now there's no script and, more importantly, no guarantee from star Andy Griffith that he'd be available for a sequel . . .

A week ago, "Return to Mayberry" scored the highest rating for a TV movie in the past couple of years, finishing second in the weekly standings to boot . . .

But reports that a sequel, aiming for a holiday audience, is on the griddle are premature, an NBC spokesman said yesterday . . .

Jim Palmer will do the play by play for the Home Team Sports cablecast of the Orioles-Blue Jays game tonight, with former Oriole teammate John Lowenstein handling the color . . .

Regular Orioles HTS announcer Mel Proctor will be in Philadelphia for an NBA broadcast . . .

ABC Sports has dropped its policy that prevented sportscasters from working a game on the network involving a team that they broadcast for in their spare time. Thus Palmer can now work Orioles games and Tim McCarver can broadcast for the New York Mets . . .

Channel 5 announces that weekend anchor Morris Jones, general assignment reporter Jackie Stone and sportscaster Steve Buckhantz have all renewed their contracts . . .

In addition, the station has hired Brian Wilson as a general assignment reporter. He's been with WKRG in Mobile, Ala. . . .

And Lesa Jansen, who has been with WLWT in Cincinnati, joins the weekend news as a producer April 30 . . .