There's nothing wrong with using tables for layout. I think that whole "anti-table" crowd are just a bunch of 3l33t1st snobs. ;-) Tables are universally supported in ALL browsers. They are from ancient days. They are stable. The are properly rendered by all browsers.
divs and spans are not. There are significant differences between ie, ff, opera, safari, etc over how things like css styles (such as "padding" or "margins") are played out in the rendering of the page.
About your question:
An [input type=submit] outside of a form will do nothing. If you want a button outside a form, you might try playing with "type=button" and see where that gets ya. You'll probably need to script a javascript action to make it do your nefarious bidding! ;-)
The other thing you might try is clearing the form's margin (by default, forms have noticeably large margins) and also try floating the FORM (ie, style="margin:0px;float:right;") or so....