Iweb to Wordpress - web designer help please!
I can't think that preserving the page file name will help. How many index.html pages are there?
Forwarding the site with a redirect may work. (I'm assuming that's what you mean by this site has moved.) Maybe there would be an advantage to having them going to your old domain and manually clicking the new URL. But at the cost of irritating your users. An automatic redirect is better for your customers.
Disclaimer: I know almost nothing about SEO and this doesn't seem like the site to find that expertise.