Create scrollable help popup box

I have a help menu which consists of 2 items to show different help files.  Instead of having the menu display the .doc files I had created, my supervisor would rather have the text embedded in the DXL file.  My question is: how do I make the dialog a specific size and add the text to the dialog without it looking like it's inside a textarea-type box like HTML?  And is it possible to make the text scrollable if it doesn't fit the height of the dialog?

And while I'm on the subject, is it possible to change the size of certain text and/or bold/italicize paragraphs in the dialog?

These dialogs will have just text and an OK button, much like many of the stand-alone products have that don't use a web site to give the help content.  I want to have the button visible at all times at the bottom of the dialog so that once someone has found what they're looking for, they can close the dialog without having to scroll through the remainder of the text.

Chris