The Tampa Bay Buccaneers, the team that passed over Heisman Trophy winners Tony Dorsett and Earl Campbell with top picks in drafts gone by, selected Auburn running back Bo Jackson with the No. 1 selection in the 51st National Football League draft today.

The selection of Jackson, the 1985 Heisman winner, served as an appetizer to the longest first round of an NFL draft since 1967 (more than four hours) and to a day full of intriguing trades of draft picks and veteran players.

The Los Angeles Raiders made what scouts called one of the most surprising first-round picks ever in University of Pittsburgh defensive end Bob Buczkowski, and went on to a fascinating futuristic choice in the fourth round, selecting running back Napoleon McCallum of the Naval Academy even though McCallum is committed to a five-year military stint. If they sign McCallum, the Raiders will retain his NFL rights upon his departure from the Navy. If they are unable to sign him by the 1987 draft, a league official said, McCallum will be open to draft by any other NFL team.

Meanwhile, San Francisco made an unprecedented six trades in the first three rounds today, including reserve quarterback Matt Cava-naugh to the Philadelphia Eagles for two draft picks (a No. 3 this year, a No. 2 next year) and a swap that allowed the Redskins to take Hawaii receiver Walter Murray with the 49ers' pick in the second round. In exchange, the Redskins gave the 49ers their No. 1 pick next year, and gained San Francisco's 10th-round choice this year.

The question now facing Tampa Bay is: will Jackson play football or baseball?

After posing for cameras with Commissioner Pete Rozelle, Jackson said in a news conference that he won't decide which sport to pursue until after the major league baseball draft on June 2. The U.S. Football League is an option, too, Jackson said.

"If the baseball draft was today [and the NFL's on June 2], the NFL people would want me to wait for their draft. I'm sticking to my guns and will wait until the baseball draft," said Jackson.

Jackson, who is expected to bargain for the richest rookie contract in NFL history, said that even a record-breaking offer from the Buccaneers won't lure him into signing before the baseball draft. "People can call me crazy, but money can't buy happiness," he said. "I've been poor all of my life. You can't miss what you've never had."

In Tampa, Buccaneers owner Hugh Culverhouse said, "The drafting of Bo may be a gamble, but it is not a gamble as to his talent . . . We are prepared to make him the highest-paid draft choice in NFL history. If it is a matter of money, we will go toe-to-toe with anyone."

Concerning the rest of the first round, start with the predictable. As expected, Atlanta selected nose tackle Tony Casillas of Oklahoma with the second pick; Houston followed by taking Purdue quarterback Jim Everett and the Colts then took Alabama defensive end Jon Hand. Tackle Jim Dombrowski of Virginia was taken by New Orleans with the sixth pick.

Now, for the surprises and the semisurprises: In Buczkowski, the Raiders went for a player relatively lowly rated by the scouting combines, projected by some as fifth- to 10th-round timber. Iowa quarterback Chuck Long wasn't taken until the 12th pick, by Detroit, lower than most observers expected. St. Louis stumped the draftniks by taking Michigan State linebacker Anthony Bell with the fifth pick. The Los Angeles Rams took an offensive tackle, Mike Schad, from Queen's University of Ontario.

The Eagles selected Ohio State running back Keith Byars, who recently had foot surgery, with the 10th pick and somehow managed to grab the running back they publicly coveted in the second round, Anthony Toney of Texas A&M. The team might have an entirely rebuilt backfield, depending on how Cavanaugh fares in his duel with veteran quarterback Ron Jaworski.

The Buffalo Bills selected Iowa running back Ronnie Harmon with their No. 1 pick (16th overall), a slightly higher selection than most observers figured the Brooklyn-bred Harmon would command. The choice also seems to send out a message from Buffalo management to Joe Cribbs, the Bills' former all-pro running back who wants to be traded. The message: if you still want a trade, your wish now is our command.

There were other intriguing moves:

*The 49ers made three choice-hoarding trades before they even made their first selection. By doing so, the 49ers parlayed their No. 1 pick (No. 18 overall) into three picks, in the second, third and fifth rounds.

Before trading Cavanaugh, the 49ers had made their first selection, taking Alabama defensive end Larry Roberts in the second round. Coach Bill Walsh had hoped to choose Iowa's Harmon, the brother of 49ers running back Derrick Harmon.

*The New York Giants traded veteran cornerback and former contract holdout Mark Haynes, 27, to Denver and traded Gary Zimmerman, a former USFL offensive lineman, to Minnesota in exchange for a total of four second-round picks (one next year) and a No. 6 this year.

With this mother lode, the Giants had six picks in the first three rounds and used all of them on defensive players, beginning with Notre Dame lineman Eric Dorsey, formerly of McLean (Va.) High School. This was an interesting tactic for a team that had the league's second-rated defense last year, behind champion Chicago's.

*The Dallas Cowboys wrecked one plan of the Giants by swapping first-round picks with the 49ers (from No. 20 to No. 18) to select UCLA wide receiver Mike Sherrard. The Giants were considering taking Sherrard with the very next pick.

This represented the first time the Cowboys had traded up in the first round since 1977 (when they got Dorsett) and the first time they had taken a receiver in the top round since 1968 (anybody remember Alabama's Dennis Homan, who had an insignificant three-year career with Dallas?).

Dallas Coach Tom Landry said, "We were afraid the Giants would take [Sherrard], so we had to do something. He was exactly what we wanted."

On Draft Day '85, the Bears had caused a big-league ruckus by taking William (The Refrigerator) Perry in the first round. Coach Mike Ditka had promised "another surprise" this year, even though the Super Bowl champions were choosing last.

The surprise came in the form of Florida running back Neal Anderson, who wasn't expected to be available by the 27th pick and who might very well become the heir to Walter Payton.

Anderson, the Gators' career rushing leader with 3,224 yards, is a 5-foot-11, 210-pound runner with breakaway speed. He said, "No one plays forever -- not even Walter Payton. I'll come in and work hard and wait my turn."