The best fonts are the ones that are present on all computers -- since most presentations are delivered and shared rather than printed, it is important to use fonts that are commonly installed.
This is an article I authored eons ago -- but it can help:
PowerPoint And Fonts
http://www.indezine.com/products/powerpoint/ppfonts.html
Have a great day.
Geetesh Bajaj, Microsoft PowerPoint MVP
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http://www.ppted.com
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