Loading Screen? Javascript?

Hello, I am in need of help really badly. I am making a game and when the splash screens start playing then finish to do Application.LoadLevel(“My Level”); it takes a long time for it too load and it tends to crash sometimes I don’t want people to get angry at me because there computers can’t load a few trees and grass in the main menu! Can you guys please help me with this?

See:

http://docs.unity3d.com/Manual/WebPlayerStreaming.html