I'm assume that you don't want border's around the inputs rather than around the form :- a form is a container for inputs, buttons etc; inputs are the individual 'fields' of a form.
Ok, to remove the border from an input; try this:
<input type="text" style="border-style:none;"/>
and for textareas:
<textarea style="border-style:none;"/>
if you want to disable borders for all inputs and textareas, add this to any applied CSS block:
input{
border-style:none;
}
textarea{
border-style:none;
}
that won't remove the background color from the inputs mind, you'll have to make them the same color as the page background. I don't know if it's possible to make them transparent; perhaps it is.
To 'hide' a button is relatively easy; but getting it to come back again might be difficult...
Try:
<input type="Submit" onclick="this.style.display = 'none';"/>
like I say, getting it to come back at the right time might be hard...
Unsolved 
