1. Global settings -> General settings -> Default blog to display. Just change it to whatever blog you want to appear as the 'home page'. (Er, actually, I'm not familiar with that skin, nor with how you made that link in the first place. Use a Free HTML widget and you can put whatever links you like into it)

EDIT: Yes, looking at the skin suggests that those links are done using widgets and my suggestion of just using a Free HTML widget would do.

2. Had no problems accessing the contact link. What's the problem you're having?

I want to the home link for blog2 and blog4 is blog1. how to do that?
Thanks.

EDIT: Just noticed the reply above mine is not from the OP. So this may not actually be relevant.

Delete whatever code/widget you're using to create the home page link. Add a Free HTML widget in the 'Menu' widget area. Add the following code into your free HTML widget:

<a href="http://fruitvale-classrooms.info/blogs2009/blog1.php">Home</a>

Do the same for all blogs.

(If you haven't I recommend reading the Documentation. b2evo can be tricky to figure out at first just by playing around with it, whilst the Docs should be able to explain all manner of things for first-timers)