Create your blog page and add an instance of Blog feature to the page. Blog must be only on a single page, it cannot be used on multiple pages because it creates friendly urls that hide real urls with pageid parameter and this must be consistent for all blog posts within the specific blog.
On your home page add an instance of FeedManager and in Feed Manager add the feed for the Blog and set it to show only 5 items per feed in settings.
Note: The blog feed url will not work at all until there is at least 1 post in the blog.
Hope it helps,