I would prefer a CSS approach to using tables for this.
I have six buttons on a horizontal row. The buttons are grouped like this:
button1 button2 button3 button4 button5 button6
The left two buttons are on the left margin and are close to each other but are not touching.
The third button is in the middle — doesn't have to be exactly centered, just separate.
The three buttons on the right are grouped together on the right margin, also not touching each other.
When the page is resized, the two buttons on the left stay on the left, while the three on the right slide back and forth with the right edge of the page.
This has to work in IE7.
Edit: If like me, you are struggling with the "layout tables vs. CSS" issue, check out this SO question. Over 600 upvotes.