Using one big table tends to make pages pause and appear.

If you nest more tables inside one big table, some browsers simply wont display anything until they have loaded everything inside that table which can make the site appear to stall.

I would suggest creating a style as below and then creat a DIV tag with this as the style

#container {
width: 760px;
border: 1px solid #000066;
margin-left: auto;
margin-right: auto;
padding: 0px;
}

Then put your code inside that. Should be pretty consisent across browsers.

(For some reason the Forum 'code' tag won't work)