How to make iFrame not have the scrolling bar

Like this:

<iframe ... scrolling="no"></iframe>

Edit: Also frameborder="0" is handy to hide the border.

The CSS property that deals with the document being larger than the viewable area is overflow.

This is commonly used to make scrollable divs as seen in this example.

The value you're looking for is: hidden which will clip the area outside of the visible range. Something like:

<iframe style="overflow:hidden;" src="URL" />

Should look nice a a widget

So for CSS properties you might want:

overflow:hidden;
border:none;
width:100px;
height:25px;"

And for iframe properties you probably want:

scrolling="no"
frameborder="0"
allowTransparency="true"

Read up on these to understand what they do, but they are the ones common to widgets like what you describe in your question. Together they should produce a good looking widget.