Keep teaserpost on all pages with excerpt text, not full text

I would like to designate two posts as teasers which will appear at the top of my page. I want them to stay there in that form, only displaying a few lines of text with image before the more-link.

Now, when I click on the read-more link I will be transferred to the actual post displaying the full content of that post. But the teaser at the top is doing the same thing. I want to keep those teasers short. How do I do that?

For now I just have
<?php the_content('read more &raquo;'); ?>
but this will display the full content when clicked.

When I use the_excerpt it will not show the more link and no images.