@tamaranna
Pages sit outside the blog structure. They are untended to be used for static content that rarely, if ever, changes. Categories and Tags cannot be assigned to static Pages. They can only be assigned to posts because blogs are supposed to be comprised of posts. Posts is where the dynamic, valuable content and discussion of it take place in a blog.
In a blog it's the Front Page that gets the visitor action, discussion 9comments) and the Google juice. Create a static front page and you cripple your blog. Create a structure based on static pages rather than posts and you kiss backlinks, Google juice and PageRank goodbye.
Is that what you want to do? If so then know then I have clarified the consequences of crippling a blog by making it into a mock website.
But if you do care about backlinks, Google juice and PageRank the n you can change the structure from mock website back to blog.