What output for sharing

I’m new to this. I need a slideshow that my macbook air will play using a vga/mac connector through a projector.

What would be the best way to share this? i.e. standalone, dvd, hd movie, etc. The file will be about 23 gb so I reason a dvd is out of the question.

That depends on the resolution your projector can deliver. In general of course the standalone player provides the best resolution.