Question About Wordpress On a Existing Website

Ok,

So i'm setting up a wordpress blog for the company I work for, and here's the situation:

The current website is kinda old and they don't really want to re-do anything on it but yet they want it to get found on google, well they are not SEO'd for crap, the keywords they want to rank for are not even on the site basically, so my question is, if I set up the blog and set it up for SEO with articles and keywords and what not, will the SE spiders crawl the blog and rank the whole webpage based off of the keywords on the blog or will it only rank the blog. I'm going to set it up in a subdomain so it will be

http://www.blog.website.com

Thanks for any help!!

im not 100% sure on your question. But if I understand you correctly it will only work for the blog that is SEO'd.

You may link each blog article to home page and it will definitely help your home page when each of your blog articles are indexed.

you can certainly tell your site map plugin to include your main site home page. That should help some.