Website SEO questions !!

I have a couple of quick questions I need help answering

(1) Are articles on strong relevant blogs the best form of links as they are in content that is relevant to the site?

(2) If you own a printing website does a graphic design blog hold relevance in Google’s eyes?

(3) The Blog I have an article on is PR5 and the URL is e.g. www.Domainname.org/featured-post-keyword-keyword this is a new blog post so on the front page for the next week and then will move through the pages. I have taken a look at page 20 (6 months ago) and this blog post has a PR of 3 and then I looked further back page 50 (1 year 2 months ago) and this had a PR of 2, does the post lose pr the further it moves back or has this older post not been spidered for a while as the home page will have grown in PR since then. Also does the blog post lose PR as it moves back or will it become stronger as it ages?

(4) If one of my page’s on the website is targeting (keyword printing) if I have it as (printed keyword) will Google see them as the same thing through semantically relationship?

(5) One of my rankings keeps dancing between 2nd position and 3rd is this normal for a new site?