Yeah do yourself a favour and don't whore the transitions, there's nothng more irratating than someone whos just learned to use PP and think's their amazing, as their actually irratating as ****.
A nice simple mellow background colour which does not detract from the text or message your putting across, and I would normaly only put bullet points in PP and use them to remind me of what I want to say, as what your saying is the presentation, PP is just a visual aid.
As for actualy using PP...it's a peice of p**s! just google PP tutorial. simple!