First one...

Definitely looks like a banyan. Ficus sp. Without seeing the leaves closer I couldn't say which species.

Hey, thanks for starting with a tropical tree! I'm going to be stumped on all the mainland ones. Maybe I'll bug you guys with a tropical tree every once in a while.
Humm... I see you're a bunch of smart guys, but with those roots it wasn't very difficult. The scientific name is Ficus bengalensis and I took the picture in Goa (India).
Here's a closer look for the botany freaks...