PDFs don't store text and fonts like other documents, they actually convert the font to vectors, that way no matter what font you use, the document displays exactly as expected. This is why searching for text inside the PDF is such a problem for 3rd party PDF Readers and why even Adobe themselves use to distribute 2 versions of Acrobat (one with text search, one without).
Another thing to keep in mind is, PDF isn't pixel exact, it's ratio exact. PDF readers generally do not use a 100% zoom level, instead most people read them at "fit to screen" or "fit to page". I point this out because I'm guessing the reason you are trying to use those new Vista/Office 2007 fonts is because of their LCD subpixel support (improves readability on LCD screens). This feature will not translate into the PDF, since the letter becomes a vector, subpixel information is lost, and even if it wasn't, becomes useless because the vector will be sized to something other than you intended at view time.