Static pages conversion/permalinks question

Hi everyone,

I first wanted to say thanks for the great product, wp is great software. it’s been a joy to work with over the years. Several years ago I set up a blog for my client using wp. I installed it in it’s own directory (/blog) and can be accessed by domain.com/blog. My client now want to now convert the static pages that reside on the root dir domain.com into wp. (eg. domain.com/biography.htm) Not a problem I thought, but there are several problems I see.

1. He would like to keep the blog and the website seperate, for both the design and the url (eg, domain.com/blog/2011/hello-world for the blog posts) and for the static website, domain.com/biography.htm

I’ve read you can copy index.php and .htaccess to the root and make several changes to the files so your newly converted static pages can still point to the root address via wp. But will the blog posts still have the /blog address in the url or will they have a new address, eg. domain.com/2011/hello-world If it does would I have to use a permalinks editor to manually add /blog to all the blog posts?

2. Because my client would like to keep this configuration would it be best to install a second wp installation on the root or another subdir just for the converted static pages, or would multisite be a better solution?

I guess the hangup is the seperation of the two, and keeping the all the urls for ranking purposes..it would be much easier to work with one wp if possible. I have close to 100 static pages to convert so crucial to figure how to proceed before the big conversion! Thanks for any help anyone can provide. Much appreciated!