Your dinosaurs are (from left to right in the last photo) a carnotaurus, an iguanodon and a brachiosaurus. I'm not completely sure on the iguanodon.
For ideas on paint schemes, just do a google image search using specific dino names as search terms, and you'll see what colors others have painted or illustrated on dinos.
I prefer to base my dinos, only because it facilitates gameplay, in that it's easier to determine when exactly a hunter is attacking a dino with a knife or spear, or when a hunter is getting stepped on.
Brachiosaur 1: "What's that smell?"
Brachiosaur 2: *looks at the bottom of his foot* "Oh man, I stepped in hunter- find me a stick."