Do you have to disable right click? It is a nuisance when I go to view source, right click, view source. Otherwise you have to put that View Source icon on IE’s toolbar.
You have a table nesting problem.
There is a TR within a TD. I would look there first. Do you have an HTML validator? I use the one built in to Homesite. It can find these kinds of problems. You might find HTMLTidy useful also (look it up in Google).
Tables can be difficult enough. When outputting them from a program, it can take a lot of debugging.
Here is a three column table example, similar to the phphelp.com homepage.
The site looks great as far as design. The font size on the menu is too small for me to read, but that can be fixed.
Instead of setting your entire bg as that image that loops on high resolutions, make a tank with the width and put the bg inside
rowspan is for up and down lol
and colspan side to side