At Bethesda Naval Hospital, retired admiral Hyman Rickover, 85, is reported recovering from a stroke. A hospital spokesman said yesterday that Rickover was admitted July 4 in serious condition and that his condition had improved to stable . . .

Greek tourism has slipped a bit since the TWA hijacking and that's why George Skoulas, Greece's general secretary of tourism, will be in town this weekend. He'll hold a press conference at the Vista Hotel and other briefings and meetings in an attempt to convince people that travel to or through Greece is safe and that there is increased airport security . . .

Nancy Reagan often lunches at the Jockey Club, but they have never seen her at the White House mess. Yesterday she went there for a birthday lunch of a Mexican platter and a cake with her staff. Her birthday was July 6 . . .

It's hard to imagine why, but newsstands around the country can't seem to get enough copies of the Playboy and Penthouse magazines featuring nude photographs of Madonna . . .

Television's "Washington Week in Review" team has signed a contract with Warner Books for a "Year in Review" book that may become an annual publication. Ron Goldfarb, the book's agent, said the program's longtime moderator Paul Duke will write an introduction. The book's essays will be written by the program's regulars, Haynes Johnson of The Washington Post, Hedrick Smith of The New York Times, Charles McDowell of the Richmond Times-Dispatch, Charles Corddry of The Baltimore Sun, Jack Nelson of the Los Angeles Times and Georgie Anne Geyer of Universal Press Syndicate . . .

One hears hours of droning testimony at a congressional hearing, but singer Tony Bennett went to the Hill Wednesday to sing for Congress to pass a resolution to award Congressional Gold Medals to the great composer and lyricist George and Ira Gershwin. Rep. Sidney R. Yates and Librarian of Congress Daniel J. Boorstin spoke on behalf of the resolution. Then Bennett, who has been appearing at Blues Alley this week, picked up a microphone at a piano that had brought into the room and sang two Gershwin songs, "Our Love Is Here to Stay" and "Who's Got the Last Laugh Now." The House banking subcommittee passed the proposal by a voice vote . . .

When Irish Ambassador Tadhg O'Sullivan arrives at his new assignment in the Soviet Union after his tour here, the Russians will understand clearly where his sports loyalties lie. Democratic Party activist Esther Coopersmith threw a going-away party for him at her home Wednesday and presented him with a Redskins T-shirt. It's in English on the front, but the back says "Washington Redskins" in Russian . . .