Firstly it is not a WordPress problem, it is either a theme problem or an issue when creating your content.
Firstly you should address the 140 errors on your homepage
Validating your code goes along way to making sure that it will render correctly across all platforms.
You are running WP Super Cache which also can't run correctly as you have errors in your theme. Simply looking at your Home Page Source code you can see this at the bottom.
<!-- Page not cached by WP Super Cache. No closing HTML tag. Check your theme. -->
Thirdly you are using WordPress 2.7.1 which is extremely outdated having been released in February 2009 the current version is 3.4.2.
Tidy up your theme and make it properly coded and think about upgrading your WordPress install then it might be a bit easier to help.