It takes some time to load. And it is not actually very clearn what the purpose of the site is when a new user just jumps to the page. You should make the theme more oriented
The answer to this question is css and html. CSS and html have recently been updated a lot and have shown new ways to use tags instead of iframe. Another reason is that some web browsers don't support it thus you will have to code a lot. Another reason is that it is hard to use iframe and it uses some extra bandwith
Love the loading using ajax at the start but your website looks web 1.0. You need to add gradients and make it look nicer. You should also do something with the images and the links so that it catches the eye yet simple.I am using firefox and your site looks a little broken up. You should really check your site on all browsers. You can also check how to make a client area for it on http://yomweb.co.cc/