A boy gets video game and gets sucked into it. He finds a cute living baby pink ball monster and a girl. I also remember there was a wolf/dog and living trees and a scene where a dam bursts and was about to flood a town. It was in color and i saw it about 2010 and english.
you don’t say whether it’s animated, but it sounds like Monster Rancher.
http://en.wikipedia.org/wiki/Monster_Rancher_%28anime%29