So if you want people to visit and order from your site, don't put any obstacles in their way. Whatever you do, don't force visitors to register. You have to create yourself an account, with a user id and password, before you can even order from Wal-Mart . Most major sites have learned not to require registration. They have also learned not to use frames.
Frames are a lot more gratifying to the site designer than the visitor.
To visitors, frames are merely confusing. Coach site so hard to understand that nearly all the text on the first page is navigation instructions. If the site were easy to navigate, Coach could use that space to present their products instead. So using frames will decrease the amount of traffic you get from search engines. None of the most heavily visited sites use frames.