make clean links, no js, descriptive anchor text Anchor text is a text that is displayed in link like: <a href="http://forums.digitalpoint.com">Digital Point Forums</a> PHP: Digital Point Forums is anchor text
You should also consider adding titles to the links that are most important, especially if you don't have much room for anchor text. The title will appear as a tooltip when anyone hovers their mouse over the link. <a href="http://forums.digitalpoint.com" title="Digital Point Forums">Forum</a> HTML: Cryo.
What also seems to work better is to place site navigation on the right insteed of left. This way your content will get spidered better, resulting in better rankings.