I guess I am lucky, I have met several famous people. The thing is, I only seem to remember the really cool ones, and the ones that were dicks.
Lawrence Taylor and Lee Trevino are real pricks.
Joe Pesci was really cool. (He grew up with my uncle, and mother.) Robert DeNiro said "nice to meet you" and then went to his trailer.
Van Halen are the coolest guys. Laid back and grounded.
Although Eddie was a little "out there."
The Offspring were funny guys. The guys in Cypress Hill were smoking weed the entire time I was talking with them. They even offered me some.
Joe Montana, Mickey Mantle, Muhammed Ali, Reggie Jackson, and Don Mattingly were very nice.
Derek Jeter was really cool in 95, then became a dick in 96. (I guess a WS ring, and becoming Rookie of the Year will do that to you.)
The original members of KISS were pretty nice. Ace and Peter were wasted. Gene is like fifteen feet tall.
Adam West (yes, the one from the Batman tv show) was hilarious.
Bruce Springsteen was very humble, I felt like he was grateful to meet me.
The Rock was a really nice guy. I grew up with his wife, and at the time worked for the same company as her, so we had something to talk about. At the time he was 6'5", and about 260+lbs.
The one thing that really makes a difference is when you approach them. If you bother someone at dinner, don't expect them to be nice to you. Famous people are just like us... some are nice, some are assholes. Most of the people I have met were at parties, backstage, or before/after a game.