Hey Leo,
If you want to use WordPress Pages, I would recommend installing the ExecPHP plug-in. If you want to include a block of custom code, you can simply enter an include statement from one of your WordPress Pages, right in the content textarea, and with the ExecPHP plug this will be executed properly.
Also, while in WordPress I would suggest disabling the Visual Rich Editor, as it is likely responsible for clobbering your code. In the just released WP 2.1, there is a tab so that you can switch in between modes easier than you can in 2.0.
Also, your search input field is too wide in Firefox.