My best advice to you is to NOT do flash.
Most flash amateurs produce very amateurish websites. Heck, I've even hired people to do flash mods to my website, and even they were incapable of producing a professional looking website.
On top of that, flash takes a long time to load, is cumbersome on lower end processors, and is a great deal more frustrating to the average surfer. People can't link to secondary pages within your site, which means that they're forced to sit through whatever silly intro you cook up. After a few times, they will simply stop coming back.
Consider this - by the time people get done with your first "page" (scene, really) of flash, they're on page 3 or 4 of my html-based site.