help to make a button bigger when sm comes closer

Hello,
i am new in flash , and i try to built a game.
I have made my hero . And i want him, when he comes closer to a thing( it's a draw that i have convert it to a button), the last one to grows.And when it is bigger and the player press enter to go him to a site. That's the main idea. But my problem is with the code for the interaction.

Can anyone help me with this?

thanx a lot

Try here