SP2010 Welcome Page and Site Structure

Question

I am learning sharepoint 2010 and enjoying. I've finally customized the masterpage as per my need and now i have two questions.

1. Which file I need to customize for homepage. a) default.aspx b)homepage.aspx

2. I want to create my site in the following manner. But dont know what will be the sequence like ..Create Site Collection first ..then Subsite?

About Us

...Company Profile

...Financial Rating

Departments

....Department A

....Department B

....Department C

Answer 1

1) Assuming you have the Publishing feature enabled, you can change your homepage to whatever you want it to be using the "Welcome Page" option in Site Settings. Choose one of the pages and customize it however you want.

2) This depends entirely on your internal policies - you will always have to create site collections before you create sites, but at the absolute simplest you will want to create a site collection for your root, then create two sites in the root site, one called "About Us" and one called "Departments", and then either create pages in those sites for Company Profile / Financial Rating etc, or create sites inside each of the already existing sub-sites for these sites. At any point you would be able to split off into site collections instead of sub-sites, which would also give you the option to split into different databases.