NEW ORLEANS (AP) — More than a dozen celebrities are participating in talks and activities for aging Americans at the national conference of the AARP this week in New Orleans.

Highlights include a Friday evening red carpet walk with Billy Crystal at a screening of his latest film, “Parental Guidance,” and a Saturday sit-down with actors Cicely Tyson, Ben Vereen and LeVar Burton, 35 years after the Emmy-winning ABC miniseries in which they starred, “Roots.”

A Saturday night concert with Nicks, Gladys Knight and Melissa Etheridge will be held at the New Orleans Arena. Other AARP conference and exposition events run Thursday through Saturday at the Ernest N. Morial Convention Center. The event is expected to attract some 20,000 people.

It will also be a presidential campaign stop for Republican Mitt Romney’s running mate, Wisconsin Rep. Paul Ryan. President Barack Obama is expected to address attendees via satellite. Both are speaking Friday about Social Security, Medicare, jobs and finances.

“We also care about what happens to our kid and grandkids, so these issues really transcend age and affect everyone in this country,” said C.B. Wismar, the vice president for AARP events.

The conference kicks off Thursday with a 2,000-plus volunteer effort where attendees will be paired with more than a dozen organizations such as Habitat for Humanity to rebuild homes, help with hurricane clean-up and make care packages for families in need.

More than 80 sessions will be held on health and fitness, relationships, finances and caregiving.

Tennis champion Martina Navratilova, who released a fitness book in 2006 called “Shape Yourself,” told The Associated Press she will participate in Thursday’s volunteer effort and lead hundreds through a Friday morning fitness class. On Saturday, she is scheduled to deliver a motivational speech.

“I encourage people to do more at whatever level they’re at to improve their quality of life,” she said. “As you get older, you have to adapt. You can do less but more often. Frequency is important and very beneficial.”

Others to attend the event are TV personality Leeza Gibbons, football star Dan Marino, gospel singer Shirley Caesar and political couple James Carville and Mary Matalin. Crystal and director Andy Fickman will walk the red carpet Friday for a screening of “Parental Guidance,” which is due out later this year and co-stars Bette Midler and Marisa Tomei.

TV host Hoda Kotb and celebrity chef Emeril Lagasse are to salute New Orleans and the city’s recovery since Hurricane Katrina seven years ago. AARP’s national conference was scheduled to be held in New Orleans in 2005 but was forced to relocate because of the storm.