The oldest SNL host is Betty White, she hosted the show on May 8th, 2010. At the age of 88 years and 111 days.
Betty White was the oldest, and I think the youngest was either Zac Effron or Drew Barrymore, and I'm leaning Drew Barrymore, but I could be wrong.
Beyonce Knowles
Bette Midler was the musical guest on May 26, 1979.
On January 13,, 2018, the guest host of "Saturday Night Live" will be actor Sam Rockwell, who stars in the acclaimed film "Three Billboards Outside Ebbing, Missouri." The musical guest: Halsey.
Steve Martin was never a cast member of Saturday Night Live, but appeared on 27 SNL shows and he guest-hosted 15 times. He made his first appearance on October 23, 1976, and he was 31 years old at the time (he was born on August 14, 1945).
Mr. Obama himself has not been a guest on Saturday Night Live. There have been two cast-members who played the president in skits-- Fred Armisen was first, and it was he you saw during the 2008 election. More recently (September 2012), Jay Pharoah has been playing the role of Barack Obama.
The musical guest on Saturday Night Live August 11 was 'Beck'.
On January 12th, 2008, the musical guest on Saturday Night Live was OneRepublic.
The cast of Saturday Night Revue - 1950 includes: Charles Coburn as Guest Perofrmer Joanne Dru as Guest Performer John Ireland as Guest Perofrmer
9/11
George Carlin
Taylor Swift was Saturday Night Live's musical guest on January 10, 2009, and she was both musical guest and host on November 7, 2009.
www.saturdaynightlive.com
The Fleet Foxes
Jason Mraz.
Kanye West
The cast of Jukebox Saturday Night II - 1989 includes: Teresa Brewer as Herself (guest) The Ink Spots as Themselves (guest) Julius LaRosa as Himself (guest) The McGuire Sisters as Thelmselves (guest) Patti Page as Herself - Host Fran Warren as Herself - guest Margaret Whiting as Herself (guest)
The guest of honor.