Depends on too many variables. The main thing isn't whether it's a blog or not, but whether the coding of the blog is SEO-friendly - compared to how SEO friendly the website is coded.
Okay. Now, I would like to know which requires more contents? Blog or Website? and which is easier to manage?
It is better if you have an article page on your site or your site must have a quality contents that tells about the products and services that you are offering. Blog is just the mirror of your website that will help rank keywords or give traffic to your site. Blog is easy to manage and you just need is to to update your article while website has need to be maintain and monitor.
Its easier in blog because site has lot of web pages that you have to work to,. Don't be confuse, these two are almost the same. Same seo strategies and techniques are applied here,.
Here is a timely link on the subject that questions whether SEs are starting to discount blogs: http://www.seobythesea.com/?p=942 Blogs are just CMSs whose features lend themselves to SEO. Those concepts can be extended to any type of site. I suggest finding a CMS that is best suited for your site concept. Then, after comparing it to a blog, identify the features it lacks which a blog has that likely help the blog out. Add those features (or an alternative way to get the same benefit) and you're golden. Best Regards, FS