In order of first to last deceased:

One of the Sumerian Kings was said to have lived for 43200 years. Bet he'd have some stuff to say.

Samuel Clemens - I'm sure we'd have a few laughs.

Tesla - so I could tell him to not take any of Edison's crap.

Hernan Cortes and Moctezuma II. Too many to list, really. But those two could clear some stuff up.

Pythagoras of Samos, the Ionian Greek philosopher.

Well, to make a slight thread drift, I remember that Steve Allen (hope you remember him) had a weekly show on tv where each week there would be different famous people sitting at a round table having fabulous discussions on many topics. It was a great show but did not last long sad to say. I think it was in the late 50's or early 60's. Can't remember the name or network. Steve was a fascinating and talented person.
Ha! it was 1981 and called Meeting of Minds. Nat as far back as I thought!

Jesus is the most obvious and desirable so I'll list three other historical figures I think it would be a hoot to hang out with for a day:
1. Ben Franklin
2. Richard Feynman
3. Ernest Hemingway (if he's anything like his character in Midnight in Paris, otherwise...)
Runner-ups: Claude Monet or Plato

For a day brightener, my choices would be:
1.) Robin Williams
2.) John Belushi
3.) Chris Farley
Wild Card) John Candy

George Harrison
Richard Nixon
George Patton

Moe
Larry
Curly
Shemp

It's 2020 I need to laugh.

In light of the 2020 Covid-craziness and the election, my first choice would be Will Rogers. He might have some choice things to say about everything.

For a historical perspective on the founding of America, the Constitution, and the dangers we face ahead, I’d go with Alexander Hamilton.

And the third would come from the group of Abraham Lincoln(60%), Isaac Asimov(25%), Art Buchwald(10%), and maybe Fritz Leiber(5%).

Thomas Jefferson and John Adams

I think the band Metric has it correct, in their song, Breathing Underwater. "You should never meet your heroes". You will likely be very disappointed...our heroes are US! You go to meet Marilyn Monroe, she had something with garlic in in for lunch. To make matters worse, she's got something stuck in her teeth.

If I had the opportunity, I think I would simply like to observe, from afar. Not like a creep though

Lots of repeats on here.

Jesus
George Washington
Ben Franklin
Ronald Regan
Donald Trump
George Patton

No politicians.

Frank Sinatra
Dean Martin
Sammy Davis Jr.

...and not during the day. Nightime.

Jefferson & Madison