The three were elected on Saturday, along with longtime Buffalo Bills owner Ralph Wilson, who at age 90 will be the oldest person ever inducted; former Minnesota Vikings guard Randall McDaniel; and the late Bob Hayes, a standout wide receiver for Dallas and the 1964 Olympic gold medalist in the 100 meters.
The induction ceremony will be Aug. 8 in Canton, Ohio.
The only candidate among the seven finalists who didn't get in was former Falcons and Eagles defensive end Claude Humphrey.
Former commissioner Paul Tagliabue was denied entry for the third straight year, not even making it past the first round of cuts.
Tagliabue, who retired in 2006 after 17 years in the job, has met strong resistance in his three years of eligibility despite the profitability and labor peace the league enjoyed during his tenure.
No such problem for Smith and Woodson in their first year on the ballot.
"I am blessed right now to be standing in front of you. I cry because I am not less than a man but because I am a man," said Smith, the career sacks leader who spent most of his career with the Bills.
"It's a great honor, a great feat," said Woodson, the former defensive back who played for the Pittsburgh Steelers, among other teams. "I'm still pinching myself a little bit, thinking it's surreal."
The moist poignant moment, however, came when Hayes' sister, Lucille Hester, read a note her brother wrote before he died in case he made the Hall of Fame.
In it, he thanked everyone from the city of Dallas to the Dallas Cowboys to the city of Jacksonville, Fla., where he grew up. Hayes died in 2002.
"Tell all my teammates I love them," he wrote.
"It didn't matter how long it took," said Hester, wearing a gray baseball cap with the words "Bob" in red and "Hayes" in blue stitched on it. "Today is here, and it is historic."
A defensive end, Smith retired five years ago with 200 sacks and made two all-decade teams. Drafted No. 1 overall in 1985, Smith had the most seasons with double-digit sacks (13) and the most postseason sacks (14 ½ ). He earned defensive player of the year honors in 1990 and 1996 with Buffalo and concluded his 19-season career with three seasons with the Redskins.
Smith previously said making the hall would be a bigger honor if two other Bills -- Wilson and wide receiver Andre Reed -- also got in the same year. He got half of his wish.
"What a phenomenal class, and especially with having Ralph Wilson, the founding owner of the Buffalo Bills, to be inducted in the '09 class as well," Smith said. "This is truly special."
Then his thoughts turned to his family.
"Just thinking about my father and all the sacrifices he and my mother made when I was a child growing up to be a man," Smith added, tearfully. "How he wanted me to have a life better than he had. I just wish he was here. He would be extremely proud of this day."
Wilson and the Titans' Bud Adams are the only original AFL members who still own their franchises. Their teams will meet in the Hall of Fame game the day after the inductions.
"It will take a couple minutes to get over the shock ... The fans in Buffalo have been great even though we haven't had much of a product lately ever since this guy left us," Wilson said, pointing to Smith.
Wilson has steadfastly kept his team in a small market while other owners bolted for the bright lights and big bucks of mega stadiums. He drew the biggest ovation at the announcement and mentioned that he'd seen every hall enshrinee perform at some point.
"Pro football to me is not about making money. It's a matter of competition, the flow of the game," he said. "People in the community become attached to a team. It gives them a quality of life.
"I had a chance to move that team. I think it would be crazy to do that."
Woodson, the 1993 defensive player of the year, also made the 1990s all-decade team. He led the NFL in interceptions in 1999 and 2002 with Baltimore, and in kickoff returns (27.3-yard average) in 1989 with Pittsburgh.
He played cornerback and safety for the Steelers, 49ers, Ravens and Raiders in a 17-season career, winning an NFL championship with Baltimore in 2001 and making Super Bowls with Pittsburgh and Oakland.
Woodson is the career leader in interception returns for touchdowns with 12.
"I don't think any of us started playing football because we wanted to be in the Hall of Fame," Woodson said. "I started playing football because my brothers played."
Thomas, who died nine years ago after he was in an auto accident while still an active player, also was on the 1990s all-decade team and was the 1989 defensive rookie of the year. He is 11th in career sacks with 126 ½.
A rushing outside linebacker who also had responsibilities in pass coverage for Kansas City, Thomas set an NFL mark with seven sacks in one game against Seattle on Nov. 11, 1990, a year in which he led the NFL with 20 sacks.
"Derrick Thomas was the cornerstone of the modern era of the Kansas City Chiefs and one of the most feared performers of his era," Chiefs owner Clark Hunt said. "Every head coach and offensive coordinator who faced the Chiefs during the 1990s knew when they came to Arrowhead Stadium they had to account for Derrick Thomas."
McDaniel was that rare guard who was as effective in pass protection as in run blocking and who could handle even the best defensive linemen single-handedly. He missed only two games in his 14-season career and was yet another member of the 1990s all-decade team.
"I never thought it would happen," McDaniel said. "It's kind of overwhelming. I accept this knowing I could not have done this without all the other offensive lineman I played with."
Said Smith: "Randall was a beast. Once he locked on to you, you couldn't go anywhere."
Hayes was the most dangerous deep threat in pro football from 1965 to 1975. Nicknamed "Bullet Bob," he twice led the NFL in touchdown catches and in average yards per reception. He also was a brilliant kick returner.
The long wait for Hayes to get into the hall -- he was a senior committee choice -- had much to do with problems he had off the field.
Hayes served 10 months in a Texas prison after pleading guilty in 1979 to delivering narcotics to an undercover officer. That "destroyed my life" Hayes wrote in his autobiography, "Run, Bullet, Run: The Rise, Fall, and Recovery of Bob Hayes." The prison term ended at about the same time he first became eligible for the hall.
Tagliabue's day still has not arrived. Critics cited his inability to place a team back in Los Angeles after the Rams and Raiders left in 1995, and said the labor agreement he pushed through in 2006 was cast aside by the owners last year.
Information from The Associated Press was used in this report.