I have developed a site on my MAC. The footer looks good in IE, Firefox, Safari, Chrome but when I look on to a PC it appears that the font is rendering differently and pushing
Fonts are going to render differently on any system you test it on. That is life on the web... as it should be. Websites aren't supposed to look identical... they are supposed to display in a variety of formats and ways.
Since you are using a web-safe font, I suspect the issue has to do with the difference between Microsoft's "ClearType" rendering and the anti-aliasing method on a Mac.
The best you can do is test using a service such as http://www.browsershots.org and be aware of the differences.
You may be tempted to use images for your text... don't do this.