Wow, major work needed on site, take a look (seo nightmare).

I have a client with existing site that seems to be created in somekind of ASP based storefront.
It seems like there is a redirect in the .htaccess that redirects the index to a dynamic link.
Then each link is dynamic with content ID's that go for days. ie: http://www.e-ternaltreasures.com/?W...2d-2e31cafac4c1

I am thinking of installing ISAPI_REWRITE ( http://www.helicontech.com ) then editing the navigation.

Anyone have experience with optimization of ASP storefront and/or URI rewrite?
Thanks for your time....

(\)emo