I remade the website for my work located at http://www.midatlantictechnologies.com. It looks fine in IE but when I try opening it up in Mozilla or Firefox it shifts some. Any ideas?
Mozilla and/or Firefox are proper, standards-compliant browsers, so they highlight the problems with your code. Internet Explorer is more forgiving of problems, so it is not a good idea to design with it.
You have a very simple design, so I recommend rebuilding the site without frames, using plain old HTML and a little bit of CSS. You will find it faster, easier to work with, and more compatible with the different varieties of browser.