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For SEO, it shouldn't really matter how your homepage is built too much, because the homepage usually isn't a whole dynamic page.
Most of the sites I play with, have dynamic content, but don't appear that way to the viewer, and do reasonably well (considering they are not optimised or have much effort put into them).
With Active Server Pages, most search engines will index .asp pages if the "?" is removed from the URL. There are products that will will automatically remove the query strings from your .asp pages and replace them with "/" marks.