The fastest way to get indexed it to obtain a link from another domain that is already indexedx and regularly cached. Submitting an XML sitemap never hurts, but you can still wait weeks, whereas a link can kick you in quick.
Yes, using Flash can hurt you, uness steps are taken to ensure that Google is aware of your pages existance, and thayt the Flash foles can be read.
The best way to get indexed and increase your search engine ranking is to get incoming links to your website from websites with a related subject matter. If the incomming links has the text you are trying to rank for as the "anchor text" of the link, it will help you to get indexed and thereby rank higher for that search term. Also understand that nothing is instant, Google loves content so first Google will index your domain name then your title then sub title then keywords and so on