Just to add my 2 cents. Use a backlinks checker to see where the links are coming from and going to from your website. Discard links from/to banned or dead sites ( usually PR0 ) and leave those with PR1 and above. You will find a sudden surge in your PR soon enough. Monitor & manage your backlinks for a consistent PR.
Here is a resource which I use
Link Checker . It will not only help you to decide which are the links you don't need but also tell which backlinks with high PR is your competitor's website using. A wonderful tool.