I'm not sure where to begin here since there are many issues. I think you should start by looking at the Web Developer's SEO Cheat sheet. http://www.seomoz.org/blog/the-web-developers-seo-cheat-sheet
pdf - http://static.seomoz.org/user_files/SEO_Web_Developer_Cheat_Sheet.pdf
and The Beginners Guide to SEO http://www.seomoz.org/beginners-guide-to-seo
Title: Most Important, Main keyword in beginning
Meta-description - No SEO, but use for SERPs call to Action and attention.
Meta-keywords - No SEO, Remove.
H1 - Important, should be one of the first things a spider crawls.
H2 - Not as important
H3 - H6 - Not important
Bold or Italic - Important - Main keyword should be bold or italic
Link Anchor Text - Important, most important links near the top, and Google will only count the anchor text for the first link. (same link)
Image Alt - all images should have Alt
Content - Content is extremelly relevant. But this section would need a whole page of explanation.