Its purely a HTML problem, you've made mistakes with some of your table/td/tr tags etc...
I suggest if you dont know HTML tables well use a designer to draw the type of table u want. Then add test to each cell. Eg
This is the whos' online, this cell is Forum Heading, this cell is announcements etc...
Then view the HTML source, and simple adapt it with the $variables in the places you need them. Easy!
