The placement of links on the page does change how effective the links are at passing pagerank and helping the linked pages rank. Here is a graphic from an article on buuteeq that shows this well:
Googlebot crawls pages with a frequency based on how much pagerank each page has. When Googlebot encounters a new section of links, it will crawl deeper when the first page it encountered had more pagerank.
To get your pages to get crawled more and to rank better, you should:
- Link to the section more often
- Use deep links into that section in addition to linking just to the main page of the section
- Use a list of several links into that section instead of just one link to the main page (never more than 10 links in a list though!)
- Make sure the links are prominent so that they get fully counted