Hey, there are various SEO techniques used....
Like social bookmarking, forum posting, classified posting, blog posting, article submission etc...
SEO in itself is a technique and it involve many techniques all should be taken at the at same time.
However if you want to compare "off page seo" and "on page seo" , than definately "on page seo" is most important.
In on page SEO, alway use unique and a quality content and ignore keyword stuffing. In off page SEO, use effective link building sources in which image optimization and wiki answering are best.
As per my experience Forum posting, blog commenting, bookmarking and article posting are the best seo techiques.
I think Blog Comments is a best technique to increase your websites backlinks. Because once you comment on any blog and its approved by blogger, Then you get a permanant dofollow link from that website.Thats why i think Blog Commentv is best techniques in SEO.
Guest posting and yahoo answering are the best SEO techniques.
There are many tehniques in SEO (search engine optimization). The best one is Social Book Marking , Forums , Article Submission or posting , blog posting , guest post. All techniques should be done systematically
Well Entire SEO Process requires ON page and OFF page optimization. There is no best SEO Technique to get rank on serach engines.
You need unique content and create links by google diversity.
Press Release is most important part of Off Page Search Engine Optimization.